University of Southern California Dissertations and Theses

The Paleontology And Stratigraphy Of The Ely Group In The Illipah Area Ofnevada

(USC Thesis Other)

The Paleontology And Stratigraphy Of The Ely Group In The Illipah Area Ofnevada

PDF

Download

Open document

Flip pages

Download a page range

Download transcript

Copy asset link

Request this asset

Transcript (if available)

Content T H E P A L E O N T O L O G Y A N D S T R A T IG R A P H Y O F T H E E L Y G R O U P IN T H E IL L IP A H A R E A O F N E V A D A b y B e r n a r d O w en L a n e A D i s s e r t a t i o n P r e s e n t e d to the F A C U L T Y O F T H E G R A D U A T E SC H O O L U N IV E R S IT Y O F S O U T H E R N C A L IF O R N IA In P a r t i a l F u lf i llm e n t of the R e q u ir e m e n t s fo r the D e g r e e D O C T O R O F P H IL O S O P H Y (G e o lo g y ) J a n u a r y 1962 UNIVERSITY OF SOUTHERN CALIFORNIA GRADUATE SCHOOL UNIVERSITY PARK LOS ANGELES 7. CALIFORNIA This dissertation, written by i. > ................... B ern a rd . .Qwan..Liane........................... under the direction of his Dissertation C om mittee, and approved by all its members, has been presented to and accepted by-the Graduate School, in partial fulfillment of requirements for the degree of D O C T O R O F P H I L O S O P H Y 7* ^ ................................4 ** ............................. Dean Date...........J a n u a r y , ...1.9.62. DISSERTATION^COMMITTEE Chairm an ........ T A B L E OF C O N TENTS P a g e A B S T R A C T . .................................... 1 I N T R O D U C T I O N ....................................................................................................... 2 L o c a t i o n ........................................................... '..................................................... 3 P r o c e d u r e ........................................................................................................... 3 A c k n o w le d g m e n t s ............................................................................................ 5 S T R A T I G R A P H Y .............................................................. . 6 G e n e r a l ................................................................................................................... 6 M i s s is s ip p ia n or P e n n s y lv a n ia n S y s t e m s ................................. 6 C h a in m a n -D ia m o n d P e a k F o r m a t i o n s .............................. 6 P e n n s y lv a n ia n S y s t e m ......................... 7 E ly L i m e s t o n e ......................................................................................... 7 H o lid a y F o r m a t i o n .............................................................................. 10 P e r m ia n S y s t e m ............................................................................................. 12 "Rib H ill" F o r m a t i o n ...................................................................... 12 TH E F A U N A ................................................................................................................... 14 F A U N A L A N A L Y S I S ................................................................................................ 19 S U M M A R Y ...................................................................................................................... 25 S Y S T E M A T IC D E S C R I P T I O N S ...................................................................... 27 R E G IST E R O F L O C A L I T I E S .......................................................................... 85 M E A S U R E D S E C T I O N S . 88 R E F E R E N C E S ............................................................................................................... 104 ii LIST OF ILLUSTRATIONS F ig u r e P a g e 1. Index M ap Showing A r e a of S t u d y ............................................. 4 2. A V iew of the E ly L im e sto n e .............................................. 8 3. S c h e m a tic S ectio n of the E ly L im e sto n e and H olid ay F o r m a tio n Showing D istr ib u tio n of D ia g n o stic F o s s i l s 11 Table 1. R an ges of D ia g n o stic F o s s i l s ..................................................... 18 P la te 1. C o r a ls . 7 3 2. F o r a m in if e r s , C o r a ls , and B r a c h i o p o d s ............................ 76 3. B r a c h io p o d s ................................................................................................ 78 4. B r a c h io p o d s .................................................................................. 81 5. B r a c h io p o d s, M o llu s c s , A rth ro p o d s, and E c h in o d e r m s .............................................................................................. 84 6. O utcrop of E ly Group in C en tral Illip ah Q u ad ran gle, W ith L o ca tio n of M e a su r e d S e c t i o n s .................................... p o c k e t iii A B S T R A C T A lth ou gh the E ly lim e s to n e is w id e s p r e a d in e a s t - c e n t r a l N evad a and Utah, its r e c o g n itio n h ith e r to h a s not b e e n r e la te d to a d e fin ite type lo c a lity , to d e ta ile d s tr a tig r a p h ic d e s c r ip t io n s , or to a d e s c r ib e d fauna. The E ly lim e s to n e is h e r e d iv id ed in to tw o fo r m a tio n s on the b a s is of p a le o n to lo g ic and lith o lo g ic e v id e n c e . A m a s s i v e , r id g e -f o r m in g se q u e n c e co n ta in in g a L o w e r P e n n s y lv a n ia n fau n a is d e s ig n a te d a s the r e s t r ic t e d E ly lim e s to n e . In the Illip ah q u a d r a n g le of N e v a d a th is f o r m a tio n is 1500 to 1600 f e e t th ick . T he lo w e r p o r tio n is c h a r a c t e r iz e d by an a s s o c ia t io n of lin o p r o d u c tid s and S p ir ife r o c c id u u s . T o w a rd the top of the s e q u e n c e the C h a e t e t e s - P r o f u s u lin e lla zo n e is w id e ly t r a c e a b le. A b o v e th is zo n e th e r e is an abundantly f o s s i l i f e r o u s , s ili c if i e d zon e in w h ic h P u n c t o s p ir if e r , H u s te d ia and R h ip id o m e lla a r e c o m m o n . C o n fo r m a b ly o v e r ly in g the E ly lim e s t o n e a r e about 700 f e e t of s ilty li m e s t o n e s n e w ly d e s ig n a te d the H o lid a y fo r m a tio n . T h is f o r m a tion a ls o c o n ta in s a p e r s is t e n t z o n e of C h a e t e t e s . The H o lid a y f o r m a tion is o v e r la in d is c o n fo r m a b ly b y c h e r t p eb b le c o n g lo m e r a t e s at the b a se of a se q u e n c e of L o w er P e r m ia n c a r b o n a te s and s a n d s to n e s . C ontinuous o u tc r o p s of both fo r m a tio n s w e r e tr a c e d fo r e le v e n m il e s in the c e n te r of the Illip ah q u a d r a n g le to e lim in a te s tr u c tu r a l c o m p lic a tio n s in m e a s u r e d s e c tio n s and to v e r if y the m a p p a b ility of the tw o f o r m a tio n s . The E ly lim e s t o n e is la r g e ly but not in v a r ia b ly in fau lt c o n ta c t w ith the u n d e r ly in g C h ain m an s h a le . The a n a ly s is of the fauna of the E ly group r e p r e s e n t s the f i r s t m o n o g r a p h ic study of a P e n n s y lv a n ia n fauna in the C o r d ille r a n r e g io n . P r e v io u s P e n n s y lv a n ia n c o r r e la t io n s w ith in the B a s in and R an ge p r o v in ce h ave had to be b a s e d la r g e ly on r a n g e s of M id -C o n tin e n t s p e c i e s , so c o n fu sio n a r o s e b e c a u s e of e r r o n e o u s id e n tific a tio n s and of d if f e r e n c e s in p o p u la tio n s of f o s s i l s in the tw o r e g io n s . Now it w ill be p o s s i ble to b a s e P e n n s y lv a n ia n c o r r e la t io n s of s o m e w e s t e r n fo r m a tio n s on a sta n d a rd fau n al s u c c e s s i o n fr o m the C o r d ille r a n r e g io n . A n a ly s is of the faunas in d ic a te s A t o k a n - D e s m o in e s ia n a g e fo r the E ly lim e s t o n e and D e s m o in e s ia n age fo r the H o lid a y fo r m a tio n . P u b lish e d r e p o r ts of m e g a f o s s i l s in d ica tin g S p r in g e r a n and M o r r o w a n age fo r the E ly lim e s to n e a re not su p p o rted by the c u r r e n t r e s e a r c h . F o s s i l r a n g e s h a v e b e e n a c c u r a te ly e s ta b lis h e d , and r a n g e s of s e v e r a l f o s s i l s h a v e b e e n ex ten d ed . F o r e x a m p le , D ia p h ra g m u s f a s c ic u la tu s w a s h e r e t o f o r e c o n s id e r e d to be an in d ex of M is s is s ip p ia n a g e , but it a ls o o c c u r s a b ove A tokan (P e n n sy lv a n ia n ) fu su lin id s in the H o lid a y fo r m a tio n . C h a e t e t e s , w h ic h is d o m in a n tly D e s m o in e s ia n in the M id -C o n tin e n t, is a ls o A tokan in the Illipah r e g io n . M o r e o v e r , tw o C h a e te te s z o n e s o c c u r in the E ly group, although p r e v io u s c o r r e la t io n s s e e m to be b a s e d on the r e c o g n itio n of only one zo n e, w ith a c c o m p a n y in g c o n fu sio n in c o r r e la t io n s . In c o m p a r is o n w ith s o m e M id -C o n tin e n t P e n n s y lv a n ia n fa u n a s, the fauna of the E ly group is s o m e w h a t m e a g e r , co n ta in in g on ly 49 g e n e r a . One g e n u s, fiv e s p e c i e s , and one s u b s p e c ie s a re d e s c r ib e d as new . 1 INTRODUCTION Scope T h is in v e s tig a tio n c o n c e r n s the fauna of L o w er P e n n s y lv a n ia n r o c k s in the v ic in ity of E ly , N e v a d a and the str a tig r a p h y of the l i m e sto n e s of P e n n s y lv a n ia n age in that a r e a . F a u n a l c o lle c t io n s w e r e m a d e fr o m s e c tio n s m e a s u r e d in d e ta il. F o s s i l s w e r e c o m p a r e d w ith s p e c ie s fr o m the m id -c o n tin e n t in o r d e r to e s t a b lis h fau n al r a n g e s fo r the L o w er P e n n s y lv a n ia n in th is p o r tio n of the G reat B a sin . L o w er P e n n s y lv a n ia n r o c k s n e a r E ly a r e r e p r e s e n t e d by the E ly lim e s to n e and the H o lid a y fo r m a tio n above it, and it is fr o m t h e s e tw o fo r m a tio n s that p a le o n to lo g ic a l c o lle c t io n s w e r e m a d e . L a w so n (1904) n a m ed the E ly lim e s t o n e in th e E ly M ining D is tr ic t. S p e n c e r (1917) m a p p ed the d is t r ic t p r im a r ily fr o m the stand p oin t of o re d e p o s its . S e v e r a l w o r k e r s h a v e stu d ie d the E ly lim e s to n e s in c e that tim e , the m o s t r e c e n t of w h ich a r e D ott (1955) and H o se and R ep en nin g (1959). In the v ic in ity of E lk o, N ev a d a , Dott d iv id ed the E ly lim e s to n e into tw o fo r m a tio n s , the M o le e n and the T o m e r a , and r a is e d the E ly to Group rank. D ott's d iv is io n s in the E lk o r e g io n a r e b a s e d p r im a r ily on lith - ology. The p u r p o se of th is stu d y is to r e la te lith o lo g ic e v id e n c e and p a le o n to lo g ic e v id e n c e and to e s t a b lis h r a n g e s of m e g a f o s s i l s that m a y be u se d in c o n ju n ctio n w ith fu su lin id d iv is io n s of the P e n n sy lv a n ia n . 2 3 L ocation When L aw son n am ed the E ly lim e s to n e , he did not s p e c ify a type sectio n , but rath er r e fe r r e d only to the v ic in ity of E ly, N evada. In and around the town of E ly, the upper p ortion of the E ly lim e s to n e is m is s in g . Thus the Illipah quadrangle w as ch o sen for this study, as in that a r e a co m p lete se c tio n s m a y be m e a s u r e d , and outcrops are e x c e l lent. The Illipah quadrangle is th irty m ile s w e s t of the tow n of E ly (F igu re 1). T his p ortion of e a s te r n N evada li e s in the B a sin and Range P r o v in c e . V alley flo o r s are about 6000 fe e t above s e a le v e l, and the m ou ntain su m m its a re 1000 to 7000 fe e t h ig h er. The reg io n is s e m i- arid and v eg eta tio n is s p a r se w ith the o c c u r r e n c e of pinon p in es and ju n ip ers beginning at about 7500 feet. S tru ctu ra lly the a r e a is m o d e r a te ly com p lex, w ith folding, faulting and th ru stin g in e v id e n c e . M ountain ra n g es tren d g e n e r a lly in a n o rth -so u th d irectio n . P r o c e d u r e F iv e stra tig ra p h ic se c tio n s w e r e m e a s u r e d w ith s te e l tape and Brunton c o m p a ss. Four of th e se se c tio n s are in the Illipah quadrangle, and one is in the "type area" n ear E ly, N evada. D etailed faunal c o l l e c tions w e r e m ade from th e se s e c tio n s and co m p a red w ith the e x te n siv e C arb oniferou s c o lle c tio n s on hand in the D ep artm en t of G eology at the U n iv ersity of Southern C aliforn ia. S ilic ifie d f o s s i ls w e r e etch ed from carbonate ro ck s w ith h y d ro ch lo ric acid. WHITE PINE 1 CO. n o ELY O CARSON CITY 50 0 50 SCALE IN MILES INDEX MAP SHOWING AREA OF STUDY FIGURE I 5 A c k n o w le d g m e n ts F ie ld w o r k fo r th is stu d y w a s m a d e p o s s ib le th rou gh a gran t fr o m the U nion Oil C om p an y. P r o f e s s o r W. H. E a s to n of th e G e o lo g y D ep a rtm en t of the U n iv e r s ity of S o u th e r n C a lifo r n ia s u g g e s te d the p r o b lem ; r e s e a r c h and p r e p a r a tio n of th is r e p o r t w e r e done u n d er h is p a tie n t g u id a n ce. P r o f e s s o r O. L. B andy and D r. R. O. Stone r e a d the m a n u s c r ip t and th e ir h elp fu l s u g g e s t io n s a r e g r e a tly a p p r e c ia te d . STR A TIG R A PH Y G en eral The E ly Group is d ivid ed into tw o fo r m a tio n s in the Illipah q uadrangle. The lo w e r of th e s e is the r e s t r ic t e d E ly fo rm a tio n . It is u n d erlain by the D iam ond P e a k quartz ite of M is s is s ip p ia n -P e n n s y lv a n ian age along the c e n tr a l and w e s te r n m a r g in of the q u adran gle. In the e a s te r n p a rts of the q u adrangle, o u tcro p s of the E ly lim e s to n e are m o s tly in fault con tact w ith the C hainm an sh a le of M is s is s ip p ia n age, but this r e la tio n sh ip is la r g e ly o b sc u r e d by a llu v ia l c o v e r . A bove the E ly lim e s to n e is the H olid ay fo r m a tio n of E a r ly P en n sy lv a n ia n age. T his la tte r fo r m a tio n r e p r e s e n ts a h ith erto u n n am ed seq u en ce and ex ten d s fro m the top of the E ly to the b a se of the Rib H ill sa n d sto n e ab ove. M is s is s ip p ia n or P e n n sy lv a n ia n S y ste m s C h a in m a n -D ia m o n d P e a k F o r m a tio n s The C hainm an fo r m a tio n is a f i s s i l e , cla y sh a le that g ra d es la te r a lly into the D iam ond P e a k quartz ite. In the Illipah q uadrangle, e la s t ic s d e c r e a s e ea stw a r d . F au ltin g at a ll lo c a lit ie s stu d ied o b s c u r e s the nature of the beds in co n ta ct w ith the E ly lim e s to n e . M o re o v er, th e r e are co m m o n ly a llu v ia l or T e r tia r y se d im e n ts along the faulted contact. 6 7 P e n n s y lv a n ia n S y ste m E ly L im e s to n e The E ly lim e s to n e is a s e r i e s of m a s s i v e , r id g e -f o r m in g lim e s t o n e s a lte r n a tin g w ith w e a k e r m e m b e r s (F ig u r e 2). The a p p e a r a n ce is one of b en ch and bluff to p o g ra p h y . In the c e n te r of the q u a d r a n g le , the th ic k n e s s r a n g e s fr o m 1500 to 1600 fe e t. L o w e s t b ed s of the fo r m a tio n cro p out alon g th e H a m ilto n road w h e r e the lim e s to n e is p la ty and s o m e w h a t a r g illa c e o u s w ith a p e c u lia r " b ir d se y e " s tr u c tu r e . T h is s tr u c tu r e c o n s is t s of v a g u e , c o n to r te d w r in k le s about o n e -h a lf c e n t im e t e r in d ia m e te r and tw o to th r e e c e n t im e t e r s ap art. The w r in k le s t h e m s e lv e s sh ow no in te r n a l s t r u c tu re, and th e ir s ig n ific a n c e is u n c e r ta in . E ls e w h e r e in the Illip ah q u a d ra n g le th is thin, p la ty m e m b e r is c o v e r e d . I m m e d ia te ly ab ove the " b ir d se y e " m e m b e r is a s e r i e s of c h e r ty m e m b e r s , th r e e of w h ic h sta n d out p r o m in e n tly b e c a u s e of the h igh p e r c e n ta g e of c h e r t and a r u st b ro w n s u r fa c e sta in . The lo w e s t of th e s e has as m u c h as 65 p e r cen t c h e r t. B ands of c h e r t a re o n e -fo u r th to th r e e in c h e s th ick , and s u r fa c e s ta in in g c a u s e s the r o c k to a p p ea r a l m o s t s o lid brow n. T he n ext fo r ty fe e t or s o a r e u n ifo r m ly lig h t in c o l or, the c h e r t bands b ein g on ly about o n e -h a lf in ch th ic k and one to tw o in c h e s a p a rt. A s e c o n d m e m b e r is about 40 f e e t th ic k and c o n ta in s 60 p e r cen t ch e r t. The th ird of t h e s e bands is s e p a r a te d fr o m lo w e r o n es by 180 f e e t of lig h t g r a y lim e s to n e in w h ic h th e r e is v e r y lit t le c h e r t. In the u p p e r m o s t of th e s e b e d s, L in o p ro d u ctu s is w e a th e r e d and s ta in e d so a s to be a lm o s t in d istin g u ish a b le fr o m the c h e r t. G e n e r a lly , F ig . 2 . A v ie w of the E ly lim e s to n e lo o k ing n orth along U. S. H ighw ay 50 w ith H am ilton road in the c e n te r le ft of the p hotograph. M e = C hainm an sh ale; Pern = m a s s iv e E ly lim e sto n e ; P e s = s ilty E ly lim e s to n e ; P e u = upper E ly l i m e stone; P h = H olid ay fo rm a tio n . 9 h o w e v e r , th is p o r tio n of the s e c t io n is not p a r t ic u la r ly f o s s i l i f e r o u s . A bove the c h e r ty p o r tio n of the E ly , th e r e a re about 600 to 700 fe e t of m a s s i v e , lig h t g r a y l i m e s t o n e s . A lth ou gh th e y c o n ta in both n o d u la r and banded c h e r t, th e y a r e not n e a r ly s o c h e r ty as the lo w e r p o r tion. C an in ia and b r y o z o a n s o c c u r about m id w a y in th is s e q u e n c e . A s ilty , w e a k m e m b e r o v e r lie s the m a s s i v e , m a in p o r tio n in the c e n tr a l a r e a of the q u a d r a n g le . The s ilt y zo n e is 80 to 90 fe e t th ick , buff c o l o r e d and e a s il y r e c o g n iz a b le th ro u g h o u t the a r e a . N in ety f e e t of c h e r ty lim e s t o n e o v e r lie the w e a k bed. T he u p p er 30 fe e t co n ta in the c o r a l C h a e te te s and th e fu su lin id P r o f u s u lin e l la . C h a e te te s o c c u r s in r u s t-b r o w n p a tc h e s r e s e m b lin g ir r e g u la r c h e r t n o d u le s. The zo n e w h ic h is w id e ly t r a c e a b le in e a s t e r n N ev a d a h a s b een d e s ig n a te d the C h a e tete s - P r o f u s u lin e lla faun. ,one by D ott (1955, p. 22 39). C h a e te te s o c c u r s p a tc h ily and a p p e a r s to be r e s t r i c t e d to the upper s ix or eig h t f e e t of the z o n e . P r o f u s u lin e lla is d is s e m in a t e d th rou gh the zo n e and is b e s t o b s e r v e d in c h e r t n o d u le s. A r ic h ly f o s s i lif e r o u s zo n e w ith a w e ll p r e s e r v e d fau n a li e s 40 to 50 f e e t h ig h e r in the s e c tio n . T h is f o s s i l i f e r o u s zo n e is th r e e fe e t th ick i n m o s t p la c e s and co n ta in s a s ili c if i e d fau n a in the Illip ah q u a d ra n g le . W h ere the f o s s i l s a r e not s ili c if i e d , the zon e can s t ill be r e c o g n ize d by the abund ance of P u n c t o s p ir if e r , H u s te d ia , R h ip id o m e lla , and b r y o z o a n s . The zo n e is t r a c e a b le fr o m the s o u th e r n lim it s of the q u a d ra n g le n o rth w a rd u ntil it is c o v e r e d by p o s t - P a l e o z o i c d e p o s its . P la ty lim e s t o n e s ab ove the s i l i c i f i e d zo n e a r e ca p p ed by a m a s s i v e lim e s to n e 55 fe e t th ick . T h is bed, w h ic h is so m e w h a t sa n d y at the top and f o s s i lif e r o u s at the b ottom , t e r m in a t e s a th ick s u c c e s s i o n of 10 m a s s iv e lim e s to n e s and r e p r e s e n ts the top of the E ly fo rm a tio n . H olid ay F o r m a tio n The H olid ay fo r m a tio n c o n s is t s of w eak, s ilty lim e s to n e s s e p a ra te d by thin n er r id g e -fo r m in g m e m b e r s (F ig u r e 3) and con tain s a high p e r c e n ta g e of s ilt and m u ch l e s s ch e r t than the u n d erlyin g E ly f o r m a tion. The H oliday fo r m a tio n r e s t s co n fo rm a b ly on the E ly and ex ten d s to the b a sa l m e m b e r of the "Rib H ill" sa n d sto n e. The n am e H oliday is tak en fro m the in term itten t r e c r e a tio n and ir r ig a tio n pond on Illipah c r e e k , S ec. 13, T. 17N, R. 58E w h ich is not n am ed on the top ograp h ic m ap . H o w ev er, the la c k of g eo g ra p h ic n a m e s n e c e s s it a t e d the coin ing of a n a m e. The type s e c tio n for the fo r m a tio n is in the SW 1/4 of S ec. 12, T. 17N, R. 58E. In the Illipah q u adrangle, the th ic k n e ss ra n g e s fro m 900 to 1000 feet. At f ir s t g la n ce, it w ould ap pear that the H olid ay fo r m a tio n could be c o r r e la te d b e c a u s e of its p o s itio n in the s e c tio n w ith the South R idge sa n d sto n e of S te e le (I960, p. 102). H o w ev er, the u p p e r m o st b ed s of the H olid ay fo r m a tio n con tain E a r ly P e n n sy lv a n ia n f o s s i l s , w h e r e a s the South R idge san d ston e con tain s P e r m ia n fu su lin id s. L o w e r m o s t in the fo r m a tio n is a thick, s ilty lim e s to n e w h ich is r e c o g n iz a b le throughout the Illipah a r e a and r e p r e s e n ts a sh arp lith o - lo g ic b rea k b etw een the H oliday fo r m a tio n and the E ly b elow . T hree hundred and tw en ty fe e t above the b a se , the slo p e is broken by a ridge of m a s s iv e lim e s to n e about 50 fe e t th ick . C h a e tetes f a v o s u s , C aninia torq u ia and D iap h ragm u s fa s c ic u la tu s a re p r e s e n t in th is bed. It can be tr a c e d by the p r e s e n c e of C h a e te te s , w h ich o c c u r s p atch ily , fo r the cr LU Q_ CO co CO oc I z < o r t V • i - F y r , . O H \ \ T -* 1 :7 o -.i r ' ~ * ■I f mm Thysanophyllum sp. -Highest Spirifer occiduus Chaetetes layer Diaphragmus fascicuiotus Fusuiinid layer Abundant Silicified fossils Chaetetes - Profusulinella Abundant Linoproductus spp. and Spirifer occiduus SCHEMATIC SECTION OF THE ELY L S . AND HOLIDAY FM. SHOWING D IS T R IB im O N OF DIAGNOSTIC FO SSILS. FIGURE 3 12 length of the Illipah q u adrangle. C aninia is m u ch l e s s c o m m o n than C h a e te te s , and D iap h ragm u s is r a r e . A bove the upper C h a e te te s zone is a s e r i e s of th in n er, s ilty m e m b e r s and r id g e -m a k e r s w h ich are g e n e r a lly u n fo s s ilife r o u s or only s p a r s e ly f o s s ilif e r o u s . B ry o zo a n s a re p r e s e n t, and a few b ra ch io p o d s are to be found, but the la tte r a r e e x tr e m e ly r a r e . N ear the top of the fo r m a tio n one s p e c im e n of the E a r ly P e n n sy lv a n ia n S p irifer occid u u s w as found. P erm ia n . S y stem "Rib H ill" F o r m a tio n In a ll a r e a s w h ere the "Rib H ill" fo r m a tio n is w e ll ex p o sed , a ch ert pebble c o n g lo m e r a te in a lim e s to n e m a tr ix fo r m s a p ro m in en t m a r k e r at the b a se . The c o n g lo m e r a te o c c u r s in a y e llo w to buff, s ilty lim e s to n e w h ic h con tain s a few p o o r ly p r e s e r v e d b r y o z o a n s. T h ic k n e ss of the c o n g lo m e r a te v a r ie s fr o m p la c e to p la c e . A t the so u th er n end of the quadrangle the c o n g lo m e r a te c o n s is t s of th r e e d istin ct b ed s ea ch about a foot th ick and se p a r a te d by b u ff-c o lo r e d lim e s to n e s , c o m p r is in g a total th ic k n e s s of about s ix fe e t. P e b b le s in the c o n g lo m e r a te are su b -a n g u la r and su b -ro u n d ed . In the c e n tr a l p o rtio n of the q u adrangle, the bed is fro m one to th r e e fe e t th ick and co n ta in s tw o thin c o n g lo m e r atic u n its. To the north, the c o n g lo m e r a te th in s to about s ix in c h e s , and the p eb b les are s m a lle r and m o r e rounded. E x cep t in a r e a s w h e re th is m e m b e r is c o v e r e d by su r fa c e d e p o s its , the c o n g lo m e r a te is t r a c e able from the sou th ern boundary of the q u adrangle n orthw ard to a point w h ere it is c o v e r e d by y ou n ger d e p o sits. 13 A bove the c o n g lo m e r a te is a s ilt y s e q u e n c e 50 to 60 f e e t th ic k w h ich is cap p ed by a lim e s t o n e c o n ta in in g the P e r m ia n c o r a l T h y s a n o - p h y llu m . In the w e s t e r n p o r tio n of the q u a d r a n g le a lo n g M o k o m o k e Ridge, the "Rib H ill" s a n d s to n e r e s t s d ir e c t ly on the C h a e te te s zo n e of the H olid ay fo r m a tio n . THE F A U N A The E ly fau na is c h a r a c t e r iz e d p r im a r ily by a p r o lific a s s o c i ation of s p ir ife r id and p ro d u ctid b ra c h io p o d s. L o w e r m o s t s tr a ta of the fo r m a tio n a r e c h a r a c te r iz e d by L in o - p rod u ctu s and S p ir ife r o ccid u u s S ad lick , the la tte r of w h ich is c o m m o n in the P o t t s v ille of Ohio. The c o r a l C an in ia is p r e s e n t h ig h er in the se c tio n , and a tab u late c o r a l, C h a e t e t e s , is a s s o c ia t e d w ith the fu su lin id P r o fu s u lin e lla in the upper th ird of the s e c tio n . N ea r the top of the s e q u en ce b ra ch io p o d s b e c o m e m o r e d iv e r s e and m o r e abundant. P a r t ic u la r ly c h a r a c t e r is t ic a r e P u n c to s p ir ife r c a m p e s t r is (W hite), a new s p e c ie s of R h ip id o m e lla and a new m a r g in ife r id . T h is zo n e of b ra ch io p o d s is 'u s u a lly s ili c if i e d as it is in the Illip ah q u ad ran gle, in w h ich c a s e a d istin c t and r e m a r k a b ly p r e s e r v e d faun a is to be se e n . The e n tir e fauna c o n ta in s 49 g e n e r a , a so m e w h a t m e a g e r n u m b er in c o m p a r is o n w ith o th er P e n n s y lv a n ia n c o lle c t io n s . H o w ev er , the E ly lim e s to n e is r ic h ly f o s s i lif e r o u s . S y s te m a tic a lly the g e n e r a are d istr ib u te d as fo llo w s: F o r a m in ife r a , fou r g e n e r a and four s p e c ie s ; c o r a ls , fiv e g e n e r a and fo u r n a m ed s p e c ie s ; one con u lariid ; b r y o z o a n s, tw o g e n e r a and tw o s p e c ie s ; b ra c h io p o d s, 21 g e n e r a and 27 s p e c ie s ; m o llu s c s , 13 gen era; t r ilo b it e s , one genus; w o r m s , one genus; c r in o id s, one g en u s. One g en u s, fiv e s p e c ie s and one s u b s p e c ie s a re d e s c r ib e d as new . A c o m p a r is o n of the E ly fauna w ith oth er P e n n sy lv a n ia n faunas 14 15 in d ic a t e s an E a r l y P e n n s y lv a n ia n a g e . T h e fa u n a d if f e r s f r o m the M o r r o w a n in s e v e r a l a s p e c t s . P r i m a r i l y t h e r e a r e f e w e r r e s i d u a l s p e c i e s f r o m th e M i s s i s s i p p i a n in th e E ly fa u n a th a n in th e M o r r o w a n . M a th e r (1 9 1 5 , p . 78) l i s t e d 18 g e n e r a an d 20 s p e c i e s w h ic h h e c o n s i d e r e d to b e r e s i d u a l in th e M o r r o w a n of O k la h o m a an d A r k a n s a s . In th e E ly l i m e s t o n e t h e r e a r e t h r e e , P u n c t o s p i r i f e r t r a n s v e r s u s (M c C h e s n e y ), D ia p h r a g m u s f a s c i c u l a t u s (M c C h e s n e y ) an d C r a n a e n a m i n u t a . T h e l a t t e r is d e s c r i b e d a s a n e w s p e c i e s , but th e g e n u s is u s u a l ly c o n s i d e r e d to b e M i s s i s s i p p i a n . In th e m id c o n t in e n t , H u s t e d ia m i s e r i M a th e r is a s s o c i a t e d w it h f o s s i l s of M o r r o w a n a g e ., A s u b s p e c i e s of H. m i s e r i , h e r e d e s c r i b e d a s n e w , o c c u r s a b o v e A to k a n f o s s i l s , h o w e v e r , an d c a n n o t be c o n s i d e r e d a s in d ic a t iv e o f M o r r o w a n a g e . T h e r e a r e o n ly t h r e e s p e c i e s in c o m m o n w ith th e R e d o a k H o l lo w fa u n a w h ic h E l i a s (1 9 5 7 , p. 5 2 6 ) c o n s i d e r e d to b e t r a n s i t i o n a l b e t w e e n th e M i s s i s s i p p i a n an d P e n n s y lv a n ia n w ith a s l i g h t l y m o r e M i s s i s s ip p ia n a s p e c t th a n P e n n s y lv a n ia n . T h e s e s p e c i e s a r e P u n c t o s p i r i f e r t r a n s v e r s u s , P . c a m p e s t r i s an d D ia p h r a g m u s f a s c i c u l a t u s . C r in o id s and b la s t o id s a r e m u c h in e v id e n c e in th e M o r r o w a n o f O k la h o m a a n d A r k a n s a s , w h e r e a s th e y a r e n o ta b ly la c k in g in th e E ly fa u n a . B e d s of c r i n o id a l d e b r is an d c o lu m n a ls do o c c u r in th e E ly f o r m a t io n , but t h e y do n o t c o m p r i s e a s ig n if ic a n t p o r t io n of th e fa u n a . O n ly on e c r in o id c a l y x is p r e s e n t in th e E ly c o l l e c t i o n s , an d t h e r e a r e n o b l a s t o i d s . It w o u ld a p p e a r th a t th e E ly fa u n a w a s d i s t i n c t l y E a r l y P e n n s y lv a n ia n , but l a t e r th a n M o r r o w a n . T h e p r e s e n c e of r e s i d u a l f o r m s 16 fro m the M i s s is s ip p ia n is c o n s id e r e d to in d ica te an ex ten d ed ra n g e fo r th e s e a n im a ls r a th e r than to in d ica te a M i s s is s ip p ia n age fo r p art of the E ly lim e s to n e . F u r th e r m o r e , the p r e s e n c e of th e s e M is s is s ip p ia n fo r m s d o es not n e c e s s a r il y in d ica te a tr a n s itio n a l sta g e b e tw e e n M i s s is s ip p ia n and P e n n sy lv a n ia n , as th ey c o m p r is e a s m a ll fr a c tio n of the to ta l n um ber of the s p e c ie s . L ittle w a s known about the S p r in g e r a n fauna u ntil E lia s pub lis h e d in 1 9 5 7 -5 8 on the R edoak H ollow fauna of so u th er n O klahom a. T h ere is no e v id e n c e that any fau n al e le m e n ts d e s c r ib e d by E lia s a r e o th er than r e s id u a l M i s s is s ip p ia n s p e c ie s in the E ly lim e s to n e . It is p o s s ib le that s o m e of the S p r in g e r a n of the m id -c o n tin e n t is the e q u iv a le n t of the M o rr o w a n . In e ith e r c a s e the E ly fauna a p p e a r s to' be n e i th er S p r in g e r a n n or M o rr o w a n in ag e. Of the b ra c h io p o d s, w h ich c o m p r is e a m a jo r p o r tio n of the fauna, m a n y h a v e d efin ite a ffin itie s w ith d e s c r ib e d D e s m o in e s ia n s p e c i e s . C o m p o sita a r g e n te a (Shepard) and L in op rod u ctu s p ra tten ia n u s {Norwood and P r a tte n )a r e not r e p o r te d b elow the D es M o in e s Group, and s e v e r a l o th e r s a re c h a r a c t e r is t ic of D e s m o in e s ia n and M iss o u r ia n . F u su lin id s and in d igen ou s b ra ch io p o d s s u g g e s t a so m e w h a t e a r lie r age than D e s m o in e s ia n , h o w e v e r . F u s u lin e lla and P r o fu s u lin e lla in the u p p e r p o rtio n of the E ly fo r m a tio n in d ica te A tokan to p o s s ib ly e a r ly D e s m o in e s ia n age fo r that p a rt of the E ly fauna. E x c e p t fo r the cep h alop od s of the. W in slow fo r m a tio n of A r k a n s a s and O klahom a, th e r e is little to c h a r a c t e r iz e A tokan m e g a fa u n a s . It is co n clu d ed that the A tokan of the G reat B a s in is c h a r a c te r iz e d by the a s s o c ia t io n of p rod u ctid and s p ir if e r id b ra ch io p o d s a s s e e n in the 17 E ly lim e s to n e in the Illipah q u ad ran gle. S p ir ife r o c c id u u s , L in o p ro d u c tus spp., P u n c to s p ir ife r c a m p e s t r is , H u sted ia rotun da, H. m i s e r i subsp. g ib b o sa , R h ip id o m ella e ly e n s is and L is s o m a r g in ife r a nuda c o m p r is e a d istin c tiv e a s s o c ia tio n of b ra ch io p o d s. T h e se f o s s i l s , a s s o c ia te d w ith the c o r a l C h a e te te s fa v o s u s and the fu su lin id s F u s u lin e lla d e v e x a and P r o fu s u lin e lla , in d ica te A tokan age (T ab le I). 18 1. C h e ste r 4. 2. S p r in g e r 5. 3. M o r r o w 6. A toka D e s M o in e s M is s o u r i 7. R e la tiv e abundance C = C o m m o n R A = Abundant = R are 1 2 3 4 5 6 7 T e x tu la r ia sp. M i lle r e lla so . P r o fu s u lin e lla aff. P . r e g ia T h o m p so n F u s u lin e lla d e v e x a T h o m p so n C h a e te te s fa v o s u s M o o re and J e ffo r d s S y r in g o p o r a sp. X C anin ia to r q u ia (Owen) L op h oph vllid iu m aff. L. p r o life r u m (M cC h esn ey ) C o n u la riid A r c h im e d e s sp. R h om b op ora le p id o d e n d r o id e s M ee k O r b ic u lo id e a c a p u lifo r m is (M cC h esn ey ) R h ip id o m e lla e l v e n s i s n. sp . iiss S c h iz o p h o r ia r e s u p in o id e s (Cox) D ie la s m a b o v id en s (M orton) C ra n a en a m in u ta n. sp. R h yn ch op ora m a g n ic o s ta M ath er W e lle r e lla sp. D e r b y ia aff. D. h a e s ita n s D unbar and C ondra C honetina f le m in g i (N orw ood and P r a tte n ) X D ia p h ra g m u s fa s c ic u la tu s (M cC h esn ey ) D ic tv o c lo s tu s a m e r ic a n u s Dunbar and C ondra A n tiq u aton ia h e rm os ana (G irty) * A n tiq u aton ia e l y e n s i s n. sp. L is s o m a r g in if e r a nuda n. gen, and n. sp. L in o p ro d u ctu s m a g n isp in u s D unbar and C ondra L in o p ro d u ctu s p ra tten ia n u s (N o rw o o d and P r a tte n ) S p ir ife r o c c id u u s S a d lick Eili N e o s p ir ife r tr ip lic a tu s (H all) C r u r ith v r is n la n o c o n v e x a (Shum ard) H u sted ia rotunda n. sp. H u sted ia m is e r i su b sp . g ib b o sa n. su b sp . o r b ic u la r is (M cC h esn ey ) C le io th y r id in a C o m p o sita a r g e n te a (Shepard) C o m p o sita su b til it a (Hall) P u n c to s p ir ife r c a m p e s t r is (W hite) P u n c to s p ir ife r tr a n s v e r s u s (M cC h esn ey ) T A B L E I.— R a n g e s of d ia g n o s tic f o s s i l s of the E ly lim e s to n e . X in d i c a te s r e p o r te d o c c u r r e n c e . # in d ic a te s s p e c ie s in the E ly lim e s to n e not p r e v io u s ly r e p o r te d in the P r o fu s u lin e lla zo n e. F A U N A L A N A L Y S IS F o r a m i n i f e r s a r e c o m p a r a t i v e l y r a r e in th e E l y l i m e s t o n e . T h e y w e r e o b s e r v e d in o n ly tw o z o n e s n e a r th e to p of th e s e q u e n c e . In t h e s e tw o z o n e s , h o w e v e r , t h e y a r e a b u n d a n t. T h e f i r s t o f t h e s e tw o z o n e s is th e C h a e te te s - P r o f u s u l i n e l l a f a u n iz o n e . S p e c i m e n s of P r o - f u s u l i n e l l a in t h is z o n e h a v e a f f i n i t i e s w ith P . r e g i a T h o m p s o n . T h e g e n u s r a n g e s f r o m l o w e r to m i d d l e A co k a n . F u s u l i n e l l a d e v e x a T h o m p - s o n o c c u r s s t r a t i g r a p h i c a l l y a b o v e th e C h a e t e t e s - P r o f u s u l i n e l l a z o n e an d h a s a r a n g e f r o m m id d le A to k a n to m i d d l e D e s m o i n e s i a n . B o th T e x t u la r ia a n d M i l l e r e l l a a r e p r e s e n t in th e C h a e t e t e s - P r o f u s u l i n e l l a z o n e of th e u p p e r p o r t i o n o f th e E ly ; h o w e v e r , t h e y a r e n o t r e f e r r e d to a n y s p e c i e s a n d a r e n o t d ia g n o s t ic a s g e n e r a . T e x t u l a r i a is e x t r e m e l y r a r e an d M i l l e r e l l a o n ly s l i g h t l y l e s s s o . S t e e l e ( I 9 6 0 , p. 1 0 0 ) r e p o r t e d M i l l e r e l l a f r o m th e b a s a l b e d s of th e E ly l i m e s t o n e , an d h e a l s o fo u n d W e d e k in d e lin a f o r m th e u p p e r b e d s . M i l l e r e l l a h a s a r a n g e f r o m L a te M i s s i s s i p p i a n to L a te P e n n s y lv a n ia n , a n d T e x t u l a r i a r a n g e s f r o m C a m b r ia n to R e c e n t . T a b u la te c o r a l s a r e r e p r e s e n t e d b y tw o g e n e r a , C h a e t e t e s a n d S y r i n g o p o r a . T h e l a t t e r o f t h e s e is c o m m o n f r o m th e e a r l y P a l e o z o i c th r o u g h th e P e r m i a n , w h e r e a s C h a e t e t e s r a n g e s f r o m M i s s i s s i p p i a n to P e r m i a n . C h a e t e t e s , h o w e v e r , is a d i s t i n c t i v e c o r a l a n d a u s e f u l o n e . In th e m i d - c o n t i n e n t C h a e t e t e s is p a r t ic u l a r ly ' a b u n d a n t an d d i a g n o s t i c in r o c k s o f D e s m o i n e s i a n a g e (D u n b a r and C o n d r a , 1 9 3 2 , p. 2 4 5 ). In th e 19 20 Hlipah quadrangle C h a e tetes is p r e s e n t b elow the h ig h e s t o c c u r r e n c e of S p irifer occid u u s w hich b rach iop od is in d ic a tiv e of E a r ly P e n n sy lv a n ia n . C h aetete s fa v o su s M ore and J effo rd s o c c u r s in tw o d is tin c t h o r iz o n s in the Illipah q u adrangle. It is p r e s e n t in the C h a e te te s - P r o fu s u lin e lla zone in the upper third of the E ly lim e s to n e . A se c o n d zone o c c u r s 320 fe e t above the E ly in the H oliday fo rm a tio n . Of the te tr a c o r a ls , C aninia to rq u ia (Owen) is the m o s t abundant. T his c o r a l w a s o r ig in a lly d e s c r ib e d fro m the B e il lim e s to n e ( M is s o u r i an) of N eb ra sk a . It has sin c e b een w id e ly r e p o r te d throughout the P en n sy lv a n ia n . In th is a r e a it ra n g e s fro m the m iddle, of the E ly to the m id d le of the H oliday fo r m a tio n above. A nother c o r a l is r e fe r r e d q u e stio n a b ly to the genus C a n in ia . In r e a lity the c o r a l r e p r e s e n ts a tr a n sitio n b etw een T r ip lo p h y llite s and C aninia. The a p p earan ce is m u ch lik e that of a C aninia w ith a n a rro w d is s e p im e n ta r iu m . The ta x o n o m ic p o sitio n of the c o r a l is u n c le a r . It cou ld be an ad van ced M is s is s ip p ia n T r ip lo p h y llite s or a p r im itiv e P e n n sy lv a n ia n C an in ia. L ophophyllidium is p r e s e n t in the E ly fauna but o c c u r s only r a r e ly . The ones that are p r e s e n t a re e x c e p tio n a lly la r g e for the gen u s. T hey have a ffin ities w ith L.~ p r o life r u m fro m the M c L e a n sb o r o f o r m a tion of Illinois; h o w e v e r , th ey a re m u ch too la r g e to be r e fe r r e d to that s p e c i e s . A r c h im e d e s r e p r e s e n ts one of the r e s id u a l e le m e n ts of M i s s is s ip p ia n age p r e s e n t in the P e n n sy lv a n ia n E ly. M ather (1915, p. 66) c ited A r c h im e d e s in P en n sy lv a n ia n ro ck s fr o m A r k a n sa s and O klahom a. H ow ever, he rep o rte d it no h igh er than the B ren tw ood lim e s to n e of 21 M o r r o w a n a g e . O ther o c c u r r e n c e s of A r c h im e d e s in the w e s t e r n s t a t e s a r e e x c e e d in g ly r a r e . C ond ra and E lia s (1944) r e p o r te d A r c h im e d e s fr o m the O q u irrh of U tah. S a d lic k h a s c o l le c t e d A r c h im e d e s fr o m the C h e s te r , S p r in g e r , M o r r o w and D e s M o in e s a ls o in U tah (E c h o ls , 1948). A r c h im e d e s sp . fr o m the E ly lim e s t o n e o c c u r s a lo n g w ith F u s u lin e lla d e v e x a of A t o k a n - D e s m o in e s ia n a g e w h ic h in d ic a te s an e x te n d e d r a n g e fo r the g en u s r a th e r th an M i s s i s s i p p i a n age fo r the o u tc r o p . A r c h i m e d e s is r a r e in th e E ly l i m e s t o n e . R h o m b o p o ra le p id o d e n d r o id e s M e e k is abundant th ro u g h o u t the E ly and is c o m m o n in m a n y P e n n s y lv a n ia n r o c k s . In a r tic u la te b r a c h io p o d s a r e u n c o m m o n in the E ly fau n a. O nly a few s p e c im e n s of O r b ic u lo id e a c a p u lif o r m is (M c C h e sn e y ) w e r e c o l le c t e d fr o m the lo w e r p a r t of the s e c t io n . T h is s p e c i e s is r e p o r te d by D unbar and C o n d ra (1932, ta b le D) fr o m the L a n s in g grou p in N e b r a s k a , and M c C h e s n e y 1 s s p e c i e s is fr o m th e D e s m o in e s ia n . The p r e s e n c e in the E ly lim e s t o n e r e p r e s e n t s an e x te n d e d ra n g e d o w n w a rd fo r th is s p e c i e s . O rthid b r a c h io p o d s a r e r e p r e s e n t e d by on ly tw o g e n e r a , but one of t h e s e , R h ip id o m e lla , is l o c a lly abundant. T he o th e r , S c h iz o - p h o r ia , is r e p r e s e n t e d by o n ly one s p e c i e s and a fe w s p e c im e n s . The R h ip id o m e lla is d e s c r ib e d a s a n ew s p e c i e s . D ott (1955, p. 2227) r e p o r te d R. n e v a d e n s is fr o m the E ly Group (T on k a fo r m a tio n ), and L a n - g e n h e im , e t a l . (I 9 6 0 , p. 151) r e p o r te d the s p e c i e s fr o m th e E ly q u a d ra n g le ; h o w e v e r , th is w r it e r h a s not s e e n t y p ic a l R. n e v a d e n s is in the E ly of the Illip ah q u a d r a n g le . R a th er it is p r e s e n t in p r e - E l y s t r a t a of P e n n s y lv a n ia n age and m a y in d ic a te M o r r o w a n a g e , w h e r e a s R. e l y e n s i s 22 r e p r e s e n ts A tokan age. D ie la s m a bovid en s (M orton) is p r e s e n t but ra r e in the c o l l e c tion s of the E ly fauna. Of m o r e s ig n ific a n c e is the p r e s e n c e of the s m a ll te r e b r a tu lid , C ra n a en a . T his genus is one of the r e sid u a l M is - s is s ip p ia n fo r m s and o c c u r s in the u p p e r m o st E ly in g rea t abundance. The s p e c ie s , d e s c r ib e d h e r e as new , is v e r y s m a ll. It w as f ir s t thought that the m y r ia d s m a ll s h e lls r e p r e s e n te d im m a tu re te r e b r a tu lid s. H o w ev er, the p r e s e n c e of g er o n tic c h a r a c t e r is t ic s in m a n y s p e c im e n s in d ica te s that th ey a r e m a tu r e . The in te r io r s of th e s e m inu te C ran aen as show c o n s id e r a b le v a r ia tio n fro m the ty p ica l f o r m s . This v a r ia tio n is m o s t lik e ly to r e s u lt from r e s o r p tio n of the b r a c h io p h o r e , a p h en om en on noted in liv in g te r e b r a tu lid s. Thus, a ll v a ria n ts w e r e d e sc r ib e d as one s p e c ie s . S tro p h o m en o id s a r e r e p r e s e n te d by tw o g e n e r a and tw o s p e c ie s . The f ir s t of th e s e , D e r b y ia , has a ffin ities w ith D. h a e s ita n s D un bar and C ondra fro m the M iss o u r ia n s e r i e s of N eb ra sk a . It o c c u r s in the lo w er E ly in beds s im ila r to the "D erb yia le d g e s" rep o rte d by Dun bar and C ondra (1932, p. 110). Thin la y e r s contain m a ts of D e r b y ia . C honetina fle m in g i (N orw ood and Pratten), o r ig in a lly d e s c r ib e d from the K an sas C ity group of M is s o u r i, is the only other strop h om en oid , and it is r a r e . The ra r ity of C honetina m a y r e su lt from e c o lo g ic a l f a c to r s, as th is genus o c c u r s m o r e c o m m o n ly in a r g illa c e o u s s e d im e n ts . P ro d u ctid b rach iop od s c o m p r is e a m a jo r p o rtio n of the fauna. M any of th e s e are ty p ica l D e s m o in e s ia n f o s s i l s . L in oproductus m a g n i- spinus Dunbar and C ondra, h o w e v er, w a s d e s c r ib e d by the authors from the A m e r ic u s lim e s to n e of la te s t P e n n sy lv a n ia n a ge. Its p r e s e n c e in I 23 the E ly lim e sto n e exten d s the range of this s p e c ie s downward c o n s id e r ably. D ic ty o c lo stu s a m e r ic a n u s Dunbar and C ondra has a w ide range although it is m o re co m m o n in the Upper P en n sylvan ian . A ntiquatonia he rm os ana (Girty) is one of the m o s t co m m o n p roductids p re se n t. A new s p e c ie s of A ntiquatonia is s m a lle r than ty p ica l r e p r e se n ta tiv e s of the gen u s. It is a ls o com m on , p a r tic u la r ly in the upper part of the E ly. An unusual m a r g in ife r id is d e s c r ib e d as new . This new genus, L is s o - m a r g in ife r a , is ty p ic a lly sm ooth ev en in s p e c im e n s w ith sp in es p r e serv ed . It is com m on in the s ilic ifie d fauna of the upper p ortion of the seq u en ce. D iaphragm us fa sc ic u la tu s (M cC hesney) is p r e se n t in the H o li day fo rm a tio n although it o c c u r s only r a r e ly - - o n ly one s p e c im e n having b een c o lle c te d . In this in sta n ce D iaphragm us o ccu rs above the C h ae- t e te s -P r o fu s u lin e lla zone w hich is d efin ite ly A tokan in age. D iap h rag m u s fa sc ic u la tu s in the H oliday fo rm a tio n is a s s o c ia te d w ith C h aetetes and is co n sid e r e d D e s m o in e s ia n in age. D iaphragm us is a r e sid u a l form from the M is s is sippian; h o w ev er, D e sm o in e sia n is apparently the you n gest age r e c o r d e d for this f o s s il. The p r e s e n c e of D iaphragm us this late in the P en n sy lv a n ia n P e r io d n eg a tes its value as an in d icator of M is s is sippian age. The s p ir ife r s , including th ree s u p e r fa m ilie s , are the m o st com m on f o s s i ls in the E ly fauna. S p ir ife r ic a e are r e p r e se n te d by S p irifer occid uu s S ad lick w hich is w id ely d istrib u ted in L ow er P e n n sylvan ian stra ta and o c c u r s co m m o n ly in the lo w er part of the E ly lim esto n e; N e o s p ir ife r tr ip lic a tu s (Hall), ty p ic a lly r e p r e se n te d in the K ansas C ity group; and C ru rith y ris p lan ocon vexa (Shumard), d e s c r ib e d 24 from the L a w ren ce sh a le of K a n sa s. The la tte r s p e c ie s is r a r e in the E ly lim e s to n e , as it is u su a lly a s s o c ia t e d w ith a r g illa c e o u s d e p o s its . R o s tr o s p ir ic a e a r e abundantly r e p r e s e n te d . Two s p e c ie s of H u sted ia a re d e s c r ib e d as new , and both a r e c o m m o n in the s ilic if ie d fauna of the upper p art of the E ly. H u sted ia rotunda n. sp. is a rotund form as o p p osed to elo n g a te shape of m o s t H u ste d ia s. The other, H. m i s e r i sub sp . g ib o s s a m o r e n e a r ly r e s e m b le s H. m i s e r i M ather but d iffe r s p r im a r ily in the an g u la rity of the c o sta e and the g ib b o sity of the v a lv e s. C leio th y rid in a o r b ic u la r is (M cC h esn ey) is a ls o a co m m o n r o s t r o s p ir if e r . It r a n g e s from the bottom to the top of the E ly s e quence and is co m m o n in P e n n sy lv a n ia n ro c k s e ls e w h e r e in the U nited S t a t e s . P u n c to s p ir ic a e a re r e p r e s e n te d by one genus and tw o s p e c ie s . P. tr a n s v e r s u s (M cC h esn ey) is a r a r e , r e s id u a l s p e c ie s from the M is - siss ip p ia n . Only one s p e c im e n is p r e s e n t in the c o lle c tio n . P . c a m - . p e s t r is (W hite) is the m o s t abundant s in g le s p e c ie s in the e n tir e fauna. It ra n g es from the lo w e r th ird of the se q u e n c e to the top w h e re th e r e is a flood of P u n c to s p ir ife r c a m p e s tr is in a s ili c if i e d zon e. M o llu sc s c o m p r is e only a s m a ll fr a c tio n of the E ly fauna. W here th ey a re p r e se n t, they a re a lm o s t a lw a y s m in u te. A la r g e E u- om phalus o c c u r s w ith F u s u lin e lla d e v e x a , but a ll other m o llu s c s are s m a ll. S om e of them m a y be m a tu r e , and so m e of them m a y h ave b een s e le c t iv e ly so r te d so that only s m a ll im m a tu r e s p e c im e n s a r e p r e s e n t. If th e s e s m a ll s p e c im e n s are m a tu r e , th ey m a y have so m e e c o lo g ic a l sig n ific a n c e; h o w e v e r , th e ir s tr a tig r a p h ic v a lu e is lim ite d . SU M M A R Y The fau n a of the E ly G roup is the f i r s t e x t e n s iv e P e n n s y lv a n ia n m e g a fa u n a p u b lis h e d fr o m the C o r d ille r a n r e g io n . A ll s p e c i e s of th is fau na h a v e b e e n d e s c r ib e d , and a ll s p e c i e s a r e fig u r e d to g e th e r fo r the f i r s t tim e . One g e n u s, fiv e s p e c ie s and one s u b s p e c ie s a r e d e s c r ib e d as new , and o th e r s h a v e b e e n r e a s s ig n e d to g e n e r a in k e e p in g w ith m o d e r n c o n c e p ts . D e s c r ip t io n s a r e b a s e d on c o lle c t io n s m a d e fr o m e x c e l le n t e x p o s u r e s in the Illip a h q u a d r a n g le , and thus a n e a r ly c o m p le te r e f e r e n c e s e c t io n h a s b e e n e s t a b lis h e d to r e p la c e the v a g u e c o n c e p t of the "type a r e a " m e n tio n e d by L a w so n . In the p r o c e s s of fie ld w o rk , fiv e s e c t io n s w e r e m e a s u r e d in d e ta il. A co n tin u o u s o u tc r o p of the E ly G roup w a s m a p p e d fo r a d i s ta n ce of 11 m i l e s in the c e n te r of the Illip a h q u a d r a n g le to e lim in a te the p o s s i b i lit y of s tr u c tu r a l c o m p lic a tio n s and to t e s t the m a p p a b ility of c o n ta c ts bounding th e tw o f o r m a tio n s . T he E ly lim e s t o n e it s e l f h a s b e e n r e s t r i c t e d to in clu d e the m a s s i v e , c lif f - f o r m in g p o r tio n of the s e q u en ce, and the H o lid a y fo r m a tio n has b e e n e s t a b lis h e d to in clu d e the s ilty , u n r e s is t a n t p o r tio n o v e r ly in g it. The fau n a of the E ly Group h a s b e e n c o m p a r e d w ith oth er P e n n s y lv a n ia n m e g a fa u n a s , and th is a s s o c ia t io n , to g e th e r w ith fu s u - l i n i d s , is the b a s is fo r the d e fin itio n of m e g a fa u n a s of A tok an and D e s m o in e s ia n a g e in the C o r d ille r a n r e g io n . The c o n ta c t b e tw e e n the A tok an and the D e s m o in e s ia n h a s 25 26 b een e s ta b lis h e d on the b a s is of the s tr a tig r a p h ic p o s itio n of fu su lin id s and m e g a f o s s i l s . C h a e te te s . a c o r a l abundant in the D e s m o in e s ia n of th e?m idcon tinent, is a s s o c ia t e d w ith P r o f u s u lin e lla , a fu su lin id d ia g n o stic of A tokan a g e. N in ety fe e t above the C h a e te te s -P r o fu s u lin e lla zone is a s ili c if i e d zo n e of b ra ch io p o d s con tain in g an a s s e m b la g e of f o s s i l s that is c h a r a c t e r is t ic of the h ig h er p art of the E ly lim e s to n e . D e s m o in e s ia n fu su lin id s a r e p r e s e n t about 180 fe e t ab ove the zo n e of b r a c h io p o d s. Thus the A to k a n -D e s m o in e s ia n co n ta ct o c c u r s in the str a tig r a p h ic s e c t io n ly in g b e tw e e n the C h a e te te s -P r o fu s u lin e lla zon e and the F u s u lin e lla zo n e at the top of the fo r m a tio n . A to k a n -D e s m o in e s ia n age is e s ta b lis h e d for the E ly lim e s to n e , and the H olid ay lim e s to n e is D e s m o in e s ia n . M ic r o f o s s ils in d ica tin g M o rr o w a n age have b een r e p o r te d fr o m the E ly lim e s to n e by oth er w o r k e r s ; h o w e v e r , th e s e r e p o r ts a r e not su p p o rted by faunal d e s c r i p tion s or fig u r e s , and the r e p o r ts w a r r a n t fu rth er study. S Y S T E M A T IC D E SC R IP T IO N S O rder F O R A M IN IF E R A F a m ily T E X T U L A R ID A E d 'O rb ig n y G enus T E X T U L A R IA D e fr a n c e , 1824 T E X T U L A R IA sp. PI. 2, fig . 6 N u m e r o u s b is e r i a l fo r a m in ife r s o c c u r in both the u p p er and lo w e r C h a e te te s z o n e s . In itial c h a m b e r s a re p la n is p ir a l, and la te r c h a m b e r s a r e b i s e r i a l l y a r r a n g e d . The s tr a tig r a p h ic ra n g e of T e x tu - la r ia in the E ly lim e s to n e is unknow n, in a s m u c h as th in s e c t io n s w e r e on ly ground of r o c k s co n ta in in g fu s u lin id s . L o c a lit y . - - 310. F a m ily F U SU L IN ID A E M o lle r G enus M IL L E R E L L A T h o m p so n , 1942 M IL L E R E L L A sp. PI. 2, fig . 5 M inute t e s t s a s c r ib e d to the g en u s M i lle r e ll a o c c u r in th in s e c tio n s groun d fr o m m id d le E ly r o c k s . The s p e c im e n fig u r e d is fr o m the C h a e t e t e s - P r o f u s u lin e lla fa u n iz o n e . L o c a lit y . - -3 1 0 . G enus P R O F U S U L IN E L L A R a u s e r - C e r n o u s s o v a and B e lja e v , 1936 D ia g n o sis . - - T e s t s m a ll, e llip s o id a l to fu s ifo r m , p r o lo c u lu s of 27 28 m ed iu m s iz e , tunnel angle ir r e g u la r , ch om ata p rom in en t and a s y m m e t ric a l. S p iroth eca c o n s is ts of th ree la y e r s: tectu m , upper and lo w er te c to r ia . PR O F U SU L IN E L L A aff. P . REGIA T hom pson, 1948 PI. 2, fig s . 3, 4 P r o fu su lin e lla from the E ly lim e s to n e is co m p a red w ith T h om p son 's s p e c ie s from Pow w ow Canyon, T ex a s. The E ly s p e c im e n s are s im ila r in s iz e , shape and the num ber of volutions but appear to be m o r e b road ly fluted tow ard the polar e x tr e m itie s than P . r e g ia . P r o fu su lin e lla in the E ly lim e s to n e is r e s tr ic te d to the C h aetetes - P r o fu s u lin e lla zone; h o w ev er, they a re quite abundant in that zone. L o c a lity . - - 310. Genus FU SU L IN E L L A M o lle r , 1877 D ia g n o s is . - -S h e ll sm a ll, fu sifo rm to elongate w ith stra ig h t a x is of coilin g. C hom ata are la r g e and a s y m m e tr ic a l. P r o lo c u lu s is s m a ll and sp h e r ic a l. S p iroth eca is co m p o sed of four la y e r s: tectu m , diaphanotheca, uppqr and lo w er te c to r ia . FU SU L IN E L L A D EV EX A T hom pson, 1948 PI. 2, fig s. 1, 2 1948. F u su lin e lla d ev ex a T hom pson, Univ. K ansas Pub., A rt. 1, p. 94; PI. 32, fig. 6, 10; PI. 35, fig s. 1-15; PI. 36, fig s . 7 -1 0 , 1 2-17. D e sc r ip tio n . - - S h ell rath er la r g e for the s p e c ie s , la te r a l slo p e s con cave and polar ends are bluntly rounded. A xis of co ilin g is straigh t, and sep ta l fluting is pronounced p olew ard although fluting con tin u es in tow ard the p ro lo c u lu s. C hom ata w e ll d evelop ed . Tunnel angle 2 9 ° in a 29 s p e c im e n 3.8 m m in len g th . L o c a lity . - - 3 1 7 . P h y lu m C O E L E N T E R A T A C la s s A N T H O Z O A S u b c la s s T A B U L A T A F a m ily C H A E T E T ID A E E d w a rd s and H a im e G enus C H A E T E T E S F i s c h e r , 1829 D ia g n o s is . - - I r r e g u la r , m o u n d -lik e c o lo n ie s of c l o s e l y p ack ed , p r is m a t ic c o r a l lit e s o c c u r r in g in v a r y in g s i z e s and sh a p e s w ith 5 to 7 im p e r fo r a te s id e s . T a b u la e a r e both c o m p le te and in c o m p le te and ran ge fr o m r e m o te to c l o s e l y s p a c e d . P s e u d o s e p ta m a y be p r e s e n t , though tr u e se p ta and m u r a l p o r e s a r e la c k in g . C H A E T E T E S F A V O SU S M o o r e and J e ffo r d s , 1945 P I. 1, f ig s . 1 -3 1945. C h a e te te s fa v o s u s M o o r e and J e ffo r d s , U niv. of T e x a s P ub. 4401, p. 191, f ig s . 207, 208. D e s c r ip t io n . - -M a s s iv e , rou n d ed to s u b c y lin d r ic a l c o lo n ie s a r e c o m p o s e d of fin e , p r is m a t ic c o r a l lit e s . T u b es a r e n e a r ly s tr a ig h t a l though th e y c u r v e fr o m th e c e n te r of th e c o lo n y so a s to in t e r s e c t the su r fa c e of the c o lo n y at r ig h t a n g le s . In t r a n s v e r s e s e c t io n the c o r a l lit e s ap p ea r g e n e r a lly u n ifo rm in both s iz e and sh a p e . T he w a lls of the c o r a llit e s ap p ea r sp o n g y and h a v e ir r e g u la r e d g e s . T he p o r o u s a p p e a r a n c e r e s u lt s fro m w a ll s t r u c tu re ra th e r than the p r e s e n c e of m u r a l p o r e s . P s e u d o s e p ta a r e p r e s e n t but r a r e . C o r a llite s a v e r a g e .3 m m in d ia m e te r . 30 T abulae m a y be p r e s e n t. W hen th ey are p r e s e n t th ey are r e m o te and often in c o m p le te . L o c a lity . - - 311. F a m ily SYRING O PO RIDAE M iln e -E d w a r d s and H aim e G enus SYR ING O PO RA G o ld fu ss, 1826 SYRING O PO RA sp. PI. 2, fig . 7 T h is c o m m o n genu s is w id e s p r e a d in P a le o z o ic ro ck s of N orth A m e r ic a and o c c u r s g e n e r a lly throughout the E ly lim e s to n e . The E ly s p e c im e n s a re a s s ig n e d to no s p e c ie s b e c a u s e the w r ite r b e lie v e s that a g r e a t d eal of w o rk m u st be done b e fo r e S y rin g o p o ra can be of any notable s tr a tig r a p h ic v a lu e. L o c a lity . - - 311. S u b c la ss T E T R A C O R A L L A F a m ily C Y A TH O PSIDA E D yb ow sk i G enus CANINIA M ic h e lin in G e r v a is, 1840 D ia g n o sis . - -S im p le , c o n ic a l to c y lin d r ic a l te tr a c o x a is in w hich the co ra llu m is u s u a lly elo n g a ted . C alyx is v a r ia b le in depth but u s u a l ly s te e p -w a lle d . M ajor sep ta a re n u m ero u s and w e ll d evelop ed , m e e t ing at the c e n te r of the co r a llu m in e a r ly sta g e s and b eco m in g a m p le x - oid in la te r s t a g e s . M inor sep ta v a r y in length . T abulae a re h o riz o n ta l and c o m p le te . The d is s e p im e n ta r iu m m a y be e ith e r w ide or n arrow , and the d is s e p im e n ts a r e u su a lly th in -w a lle d .. ? CANINIA sp. A A few s m a ll c o r a ls that r e p r e s e n t a tr a n sitio n from 31 T rip lo p h y llite s to C aninia o c c u r in the E ly lim e s to n e . T h e se c o r a ls a re s m a ll c e r a to id fo r m s that str o n g ly r e s e m b le T r ip lo p h y llite s , y et th ey h ave a n arrow d is s e p im e n ta r iu m that p e r s is t s into the upper r e gions of the c o r a llu m . T h e se c o r a ls o ccu r ir r e g u la r ly and th e ir ta x o n o m ic p o sitio n is u n certa in . CANINIA TORQUIA (Owen, 1852) PI. 1, f ig s . 4 -6 1852. C yathophyllum torq u iu m Owen, G eol. Rept. W isc o n sin , Iowa, M in n eso ta , tab. 4, fig. 2. 1944. C aninia torq u ia (Owen), E a sto n , W. H., Jour. P a l., v o l. 18, pp. 11 9 -1 3 2 , pi. 22, fig s . 2 -7 . D es c r ip tio n . - -S im p le , c y lin d r ic a l co ra llu m w ith deep, s tr a ig h t-w a lle d c a ly x . F lo o r of the c a ly x is fla t w ithout a b o s s . In tr a n s v e r s e s e c tio n of one la r g e s p e c im e n 42 m m in d ia m e te r , 48 m a jo r sep ta a re p r e s e n t. T h e se se p ta a re u ndilated and exten d s lig h tly m o r e than h alf the d ista n c e to the cen te r of the c o r a llite . M inor se p ta a re sh ort, b ein g about o n e-fo u rth as long as the m a jo r sep ta. D is s e p im e n - tarium exten d s a little l e s s than h a lf the d ista n ce to the c e n te r of the c o r a llu m . D is s e p im e n ts o ccu r in tw e lv e to fo u rteen r a n g e s , the f ir s t s ix or so bein g c o n c e n tr ic and the in n e r m o s t on es being a rra n g ed in a h errin g b o n e p attern . In longitu d in al se c tio n , tabu lae are c lo s e ly sp a ced , about ten in ten m il lim e t e r s , fla tten ed to gen tly d e p r e s s e d in the m id d le , and r e fle x e d d is ta lly . D is c u s s io n . - - T his C aninia is slig h tly la r g e r than the ty p ica l C. torq u ia and has a w id er dis se p im e n ta r iu m . 32 L o c a lity . - - 3 2 2 , 325, 326. F a m ily L O PH O PH Y L L ID IID A E M oore and J effo rd s LO PH O PH Y LLIDIU M aff. L. P R O L IF E R U M (M cC h esn ey, I860) PI. 1, fig . 7 Two w e ll p r e s e r v e d s p e c im e n s of L ophophyllidium show m a r k e d a ffin itie s w ith L. p r o lif e r u m . One s p e c im e n is 46 m m long and 18 m m in d ia m e te r at the c a ly x . T his s p e c im e n h a s the fo llo w in g se p ta l form u la: K 9 A 4 C 4 A 8 , thus 29 m a jo r sep ta . Both s p e c im e n s are e x c e p tio n a lly la r g e fo r the genus; h o w e v e r , th e sep ta l co n fig u ra tio n r e s e m b le s that of L. p r o lif e r u m . L o c a lity .- - 3 0 9 . C la s s SC Y PH O ZO A O rder C O NULARIIDA M ille r and C u r le y F a m ily CONULA R IID AE W alcott C ONU LARIIDS PI. 5, fig . 27 One s p e c im e n p r e s e r v e d as an e x te r n a l m o ld is r e fe r r e d to th is group. The s p e c im e n is fr a g m e n ta l and w a s c o lle c te d fro m the b a se of the E ly lim e s to n e . L o c a lity . - - 31 3. P h ylum BR YO ZO A O rder C YC LO STO M A TA F a m ily F E N E S T E L L ID A E King G enus A R C H IM ED ES Owen, 1838 D ia g n o s is .- - F e n e s t r a t e fron d s s p ir a lly tw iste d about and 33 su p p o rted by a s c r e w - l i k e sh a ft of c a lc iu m c a r b o n a te . Z o a r ia l n etw o rk is fu n n e l-sh a p e d , and z o o e c ia a r e d is p o s e d in tw o r o w s a lo n g the b r a n c h e s. C a rin a e m a y be p r e s e n t on the o b v e r s e s id e of th e fron d . D is s e p im e n ts a r e n o n p o r if e r o u s . A R C H IM E D E S sp. P I. 5, fig . 30 D e s c r ip t io n . - - A x is c o n ta in s ten v o lu tio n s in a d is ta n c e of 7.5 cm . Shaft is 2 .9 m m in d ia m e te r at the b a s e of the fla n g e and 5.5 m m at the top. The s u r fa c e of the sh a ft is f in e ly s tr ia te . V o lu tio n h eig h t a v e r a g e s 7 .5 m m . F r o n d s a r e not a tta c h e d to th e s p ir e of the s p e c im e n in th is c o lle c tio n , alth ou gh the s p ir e r e s t s in a h a s h of f e n e s t e llid d e b r is . F e n e s t r u le s a r e e lo n g a te and b lu n tly rou n d ed at e ith e r end. W idth of f e n e s t r u le s if 3.5 m m , and the le n g th -w id th r a tio is th r e e to one. B r a n c h e s a r e n a r r o w and c l o s e l y sp a c e d , a v e r a g in g 3.7 m m in w idth. D is s e p im e n ts a r e 1 m m in w id th , s m o o th and s e t b e lo w the s u r fa c e of the fron d . A p e r tu r e s a r e ro u n d ed and a lt e r n a te ly sp a c e d on e ith e r sid e of a s tr o n g ly p ro n o u n c e d c a r in a a t a d is ta n c e of about 0 .3 m m . D is cus s io n . - - T h is s p e c i e s of A r c h im e d e s o c c u r s w ith F u s u lin e lla d e v e x a of M id d le P e n n s y lv a n ia n a g e . It d iffe r s fr o m o th er s p e c ie s r e p o r te d in p o s t - M i s s i s s i p p i a n r o c k s p r im a r ily in the g r e a te r len g th of its v o lu tio n s . L o c a lit y . - - 318. F a m ily R H A BD O M ESID A E Vine G enus R H O M BO PO R A M eek , 1872 D i a g n o s i s - B ra n ch in g b r y o z o a n s w ith z o o e c ia a lte r n a te ly a r ra n g ed in r o w s. A p e r tu r e s a re ov a l. D ia p h ra g m s a r e p r e s e n t. W alls in the m a tu r e r e g io n a re m u c h th ic k e r than in the im m a tu r e r e g io n . Both m e g a - and m ic r a c a n th o p o r e s a r e p r e s e n t. It is the rh o m b o id a r r a n g e m e n t of the la tte r alon g an aca n th o p o re r id g e that g iv e s the genus its n a m e. R H O M B O PO R A L E PID O D E N D R O ID E S M eek, 1872 1872. R h om b op ora le p id o d e n d r o id e s M eek , U. S. G eol. S urv. N e b r a sk a , p. 141, PI. 7, f ig s . 2 a - f . D e s c r ip tio n . - - B r a n c h e s a re s m a ll, a v e r a g in g 2.5 m m in d i a m e te r . A p e r tu r e s a r e elo n g a te oval, 0 .3 m m in le n g th and 0 .1 5 m m in w idth. M e g a c a n th o p o r e s a r e p r o m in e n t and w e ll d ev elo p e d , b ein g about h alf the d ia m e te r of the a p e r tu r e s . M ic r o p o r e s a r e p r e s e n t but a r e d ifficu lt to d is tin g u is h on w e a th e r e d s u r fa c e s . D is cu s s io n . - - T h is R hom b op ora is s o m e w h a t la r g e r than ty p i ca l r e p r e s e n ta tiv e s of the s p e c i e s . H o w ev er , its w id e range th roughout the E ly group lim it s its s tr a tig r a p h ic v a lu e . P h ylu m BR A C H IO PO D A C la s s IN A R T IC U L A T A F a m ily DISCINIDAE G enus O R B IC U L O ID E A d'O rbign y, 1847 D ia g n o s is In eq u ivalve in a r t ic u la t e s , s u b e llip tic a l in o u tlin e. V en tra l v a lv e is n e a r ly fla t w ith an e c c e n tr ic ap ex. An elo n g a te d p e d i- 35 c le g r o o v e e x te n d s fr o m the a p ex n e a r ly to p o s t e r io r m a r g in of the s h e ll. O R B IC U L O ID E A C A P U L IF O R M IS (M c C h e sn e y , 1860) PI. 2, f ig s . 8, 9 1860. P i s c in a c a p u lifo r m is M c C h e s n e y , D e s c . N ew P a l. F o s s i l s , p. 72. D e s c r ip tio n . - -S h e ll is s u b c ir c u la r in o u tlin e. F la tte n e d p e d i c le v a lv e h a s an e lo n g a te d fo r a m w h ic h is bounded on e ith e r s id e by lo w , rou n d ed r id g e s . A p e x is lo w and p o s t e r io r . G row th lin e s a p p ea r d is tin c tly fla t and a r e w id e r at the a p e x than at the m a r g in s of the v a lv e . In a s h e ll 2.1 cm in d ia m e te r th e r e a r e 31 g ro w th lin e s in a d is ta n c e of 1 cm . T h e s e lin e s a p p ea r o c c a s io n a lly to b ifu r c a te and m a y r e s u lt fro m ir r e g u la r grow th . B r a c h ia l v a lv e is an e c c e n t r ic co n e, the m a r k in g s of w h ic h a r e lik e th o se of the p e d ic le v a lv e . The a p e x sta n d s 1.2 cm h ig h in a s h e ll 2.2 cm lon g. The la r g e s t s h e ll in th is c o lle c t io n is a v e n t r a l v a lv e w h ich m e a s u r e s 3.1 cm in le n g th and 2 .8 cm in w idth . L o c a lit y . - - 31 3. C la s s A R T IC U L A T A O rd er P R O T R E M ID A -T E L O T R E M ID A S u b o rd er ORTH IN A S u p e r fa m ily O R TH ICAE F a m ily R H IP ID O M E L L ID A E G enus R H IP ID O M E L L A O e h lert, 1890 D ia g n o s is . - -A p u n ctate orth id , b ic o n v e x , s u b c ir c u la r in o u tlin e. H in g e -lik e sh o rt, c a r d in a l a r e a s m a ll. In te rn a lly the ad d uctor m u s c l e - s c a r s a re fla b e lla te and 36 b ounded b y a m a r g in a l r id g e . T h e y m a y or m a y not s u r r o u n d th e d id u c - to r s c a r s . R H IP ID O M E L L A E L Y E N S IS n. sp . P I. 2, f i g s . 1 1 -1 6 D e s c r ip t io n . - - S h e ll is s m a ll, su b o v a te in o u tlin e , abou t as w id e as it is lo n g . G r e a t e s t w id th is ju st a n te r io r to th e m id d le of the s h e ll. S h e ll su b e q u a lly b ic o n v e x , b r a c h ia l v a lv e m o r e or l e s s e v e n ly c o n v e x , a n te r io r h a lf of the p e d ic le v a lv e is a lm o s t fla t, b e c o m in g g ib b ou s in th e u m b o n a l r e g io n . S u r fa c e of both v a lv e s is m a r k e d by n u m e r o u s , h o llo w li r a e , the o p e n in g s o f w h ic h p r o d u c e a p u n c ta te s u r f a c e . L ir a e in c r e a s e by in te r c a la tio n . A lon g the lin e of c o m m i s s u r e , 70 to 110 lir a t io n s m a y be c o u n ted on m a tu r e s p e c im e n s , th e a v e r a g e b e in g about fo u r p e r m i l l i m e t e r . C a rd in a l a r e a of both v a lv e s is q u ite s m a ll, th at of the p e d ic le v a lv e b e in g in c u r v e d , w h e r e a s th a t of th e b r a c h ia l v a lv e is a lm o s t in a p la n e w ith the lin e of c o m m i s s u r e . T h e h in g e lin e is about o n e -fo u r th the w id th of th e s h e ll. D im e n s io n s of an a v e r a g e s p e c im e n a r e as f o l lo w s: le n g th 11 m m , w id th 11 m m , th ic k n e s s 4 .8 m m . S iz e s r a n g e fr o m ju v e n ile f o r m s of 3 m m in le n g th to adult s p e c im e n s 13 m m in le n g th . In te r n a lly the p e d ic le v a lv e b e a r s la r g e , fla b e lla t e d id u c to r m u s c le s c a r s th at su r r o u n d an e le v a t e d p la tfo r m w h ic h in tu rn b e a r s the s le n d e r ad d u cto r s c a r s . T he d id u c to r s c a r e x te n d s a n t e r io r ly tw o - th ir d s of the le n g th of the v a lv e . Stout d en ta l la m e l la e d iv e r g e and c o n tin u e onto the flo o r of th e v a lv e w h e r e th e y fo r m a s lig h t r id g e a ro u n d the d id u cto r s c a r s . T h is r id g e is m o r e p r o n o u n c e d a lo n g th e a n t e r io r 37 of the sc a r than along the la te r a l m a r g in s . M u sc le p a tte r n s of the b r a c h ia l v a lv e a re s m a ll and in d istin ct. The ca rd in a l p r o c e s s is s m a ll and d o es not exten d onto the flo o r of the v a lv e as in so m e s p e c ie s . C ru ra l p r o c e s s e s a re stout and d iv er g in g . D is c u s s io n . - - R h ip id o m ella e ly e n s is d iffe r s fro m R. ca r b o n a r ia (Sw allow ) in that R. e ly e n s is is la r g e r , l e s s gibbous and h as fin er and m o r e c lo s e ly sp a c e d lir a tio n s . It d iffe r s fro m R h ip id o m ella n e v a d e n s is (M eek) in that it is s m a lle r than R. n e v a d e n s is and so m ew h a t l e s s g ib b ou s. L o ca lity . - - 309. Super fa m ily D A L M A N E L L IC A E F a m ily SCHIZ OPHORIIDAE G enus SCH IZOPH ORIA King, 1850 D ia g n o s is . - - E lon gate to t r a n s v e r s e , su b c ir c u la r orth id s w hich are m a r k e d ly b ic o n v e x and in w h ich the p e d ic le v a lv e is u su a lly m u ch m o r e gibbous than the b r a c h ia l v a lv e . In te r a r e a s are s m a ll to a lm o s t o b s o le te . The a n te r io r m a r g in m a y be sin u ate as a r e s u lt of a sh allow p e d ic le sin u s. The su r fa c e is lir a te w ith c o n c e n tr ic grow th lin e s p ro m in en t on the a n te r io r third of the sh e ll. The in te r io r of the p e d ic le v a lv e is m a rk ed by a p ro m in en t m ed ia n sep tum and str o n g dental la m e lla e w hich exten d out onto the flo o r of the v a lv e . A l e s s p r o m in e n t sep tu m is p r e s e n t on the b r a ch ia l v a lv e . D isc u s s io n . - - The d ia g n o s e s of S ch izo p h o ria and R h ip id o m ella d iffer only slig h tly , the c h a r a c te r is tic d iffe r e n c e b ein g in tern a l. 38 S c h iz o p h o r ia h a s a m e d ia n se p tu m and d en tal la m e lla e that ex ten d onto the flo o r of the s h e ll, w h e r e a s R h ip id o m e lla h as no m e d ia n sep tu m and the d en ta l la m e lla e m a y be c o n s id e r e d to su rro u n d the m u s c le s c a r s as e le v a te d r id g e s . SC H IZ O PH O R IA R E SU P IN O ID E S (C ox, 1857) PI. 2, f ig s . 1 7 -1 9 1856. S c h iz o p h o r ia r e s u p in o id e s (C ox), G eo l. S u rv. K entucky, v o l. 3, p. 570, p i. IX, f ig s . 1-lb . D e s c r ip t io n . - - S h e l l is su b q u a d ra te in ou tlin e, w id th about o n e - fo u rth g r e a te r th an le n g th . V a lv e s su b e q u a lly b ic o n v e x , the b r a c h ia l v a lv e b e in g m o r e gib b ou s than the p e d ic le . H in g e -lin e sh o r t, about o n e - th ird the w id th of the s h e ll. L in e of c o m m is s u r e is d is tin c tly r e s u p i- n a te. P e d ic le v a lv e b e a r s a b ro a d , s h a llo w s u lc u s . The s u r fa c e of both v a lv e s is lir a t e . On the in te r io r of the p e d ic le v a lv e tw o thin, d en ta l la m e lla e bound a n a r r o w m u s c le fie ld and ex ten d s lig h tly m o r e than o n e -th ir d the d is ta n c e to the a n te r io r ed g e of the v a lv e . A n a r r o w m e d ia n sep tu m sta n d s w e ll ab ove the flo o r of th e v a lv e and b is e c t s the m u s c le fie ld . C r u r a l la m e l la e ex te n d fr o m th e b ea k of the b r a c h ia l v a lv e about o n e -th ir d the d is ta n c e to the a n te r io r . T h e s e la m e lla e a r e s h o r t e r and m o r e w id e ly d iv e r g e n t th an th o se of the p e d ic le v a lv e . A low m e d ia n r id g e sta n d s ab ove the flo o r of th e v a lv e but d o es not ex ten d fr o m the b eak . The s in g le s p e c im e n in th is c o lle c t io n m e a s u r e s 3.1 m m in w id th, 2 .6 m m le n g th and 1.7 m m in t h ic k n e s s . L o c a lity . - - 312. 39 S u border T E R E B R A T U L IN A S u p e r fa m ily T E R E B R A T U L IC A E F a m ily D IE L A SM A T ID A E Genus D IE L A SM A King, 1859 D ia g n o s is . - - T e r e b r a tu lid s h e lls w ith p u n ctae q u in c u n x ia lly a r ran ged . S h e lls a r e sm o o th alth ou gh gro w th lin e s m a y c a u s e i r r e g u l a r i t ie s in g e r o n tic fo r m s . F o ld and s u lc u s m a y or m a y not be p r e s e n t. B eak is in cu rv e d , in te r a r e a is s m a ll. The in te r io r is c h a r a c t e r iz e d by a sh o rt, r e c u r v e d lo o p . T h is loop a r i s e s fr o m the c r u r a l p la te s , d e s c e n d s into the p e d ic le v a lv e and is r e c u r v e d into the b r a c h ia l v a lv e . D IEL A SM A BO V ID ENS M orton , 1836 P L 4, fig . 15 1836. T e r e b r a tu la b o v id en s (M orton), A m . Jou r. S c i., v o l. 29. p. 150. D is c u s s i o n . - - Tw o s p e c im e n s fr o m the lo w e r E ly a r e a s s ig n e d to th is w id e ly d istr ib u te d s p e c ie s on the b a s is of e x te r n a l fo r m only. T h e se la r g e te r e b r a tu lid s ap p ear to fit the c o n c e p t of D. b o v id en s in shape, but the gen u s is b a s e d on in te r n a l f e a t u r e s . L o c a lit y . - - 31 3. F a m ily T E R E B R A T U L ID A E G enus C R A N A E N A H all and C lark, 1893 D ia g n o s is .- -S m a ll te r e b r a tu lid s w ith elo n g a te s h e lls , s u b e r e c t b ea k s and rounded fo r a m e n s . Both v a lv e s a r e m a r k e d ly c o n v e x though the p e d ic le v a lv e is m o r e so . T h is gen u s is c h a r a c t e r iz e d by th e n atu re of the c a r d in a lia . The h in ge p la te is f r e e , c o n c a v e and p e r fo r a te . 40 C r u r a o r ig in a te n e a r th e a n te r io r m a r g in s of the p e r fo r a tio n , thus fo r m in g d is tin c t r id g e s on the v e n t r a l s u r f a c e of th e c a r d in a l p la te . S tro n g d en ta l l a m e l la e su p p o r t th e h in g e t e e t h on th e p e d ic le v a lv e . T h e s e la m e l la e m a y or m a y not b e f u s e d to th e s h e ll w a ll. S h e ll m a tte r ' is p u n ctate; b r a c h id iu m is s h o r t and D i e l a s m a - l i k e . C R A N A E N A M IN U T A n. sp . P I. 4, f i g s . 1 6 -2 1 D e s c r ip t io n . - - S h e ll is t y p ic a lly t e r e b r a t e l l i f o r m , b ic o n v e x and e lo n g a te w ith g r e a t e s t w id th a n t e r io r to m i d - r e g i o n of th e s h e ll. A n t e r io r c o m m i s s u r e is r e c t im a r g in a t e to u n ip lic a te , b e a k in c u r v e d , p e d ic le fo r a m e n rou n d ed . B r a c h ia l in t e r io r is c h a r a c t e r iz e d b y a p e r f o r a t e , f r e e h in g e p la te . T h e p o s t e r i o r en d of the p la te is b lu n tly m u c r o n a te , and th e p la te is w id e r than l o n g - - t r a n s v e r s e l y o v o id . T h e l a t e r a l p o r tio n s a r e rou n d ed , and th e r e is a s lig h t r e e n t r a n t a lo n g th e la t e r a l m a r g in of the p la te . T he p e r f o r a t io n is e lo n g a te to o v a l and is in th e c e n t e r of the p la te . At the p e r fo r a tio n , the p la te is d e e p ly c o n c a v e . C ru ra o r ig in a te n e a r the a n t e r io r en d of th e p e r fo r a tio n , d i v id in g the p la te into t h r e e d is t in c t r e g i o n s . A t th e a n t e r io r m a r g in of the p la te , tw o c r u r a l p r o c e s s e s e x te n d u p w a rd to w a r d the p e d ic le v a lv e fo r a s h o r t d is t a n c e . T he D i e l a s m a - li k e lo o p of th e b r a c h id iu m is e lo n g a te , e x te n d in g a p p r o x im a t e ly h a lf th e d is ta n c e of th e v a lv e . P e d ic le in t e r io r is m a r k e d by sto u t d en ta l la m e l l a e w h ic h e x ten d to the flo o r of the v a lv e but n o t out onto th e f lo o r . T h e s e la m e lla e m a y be a d ja c e n t and f u s e d to th e s id e s of the s h e ll s o a s to fo r m r id g e s a lo n g the s id e of the s h e ll, or th e y m a y be d ir e c t e d m o r e n e a r ly to w a r d 41 the c e n te r of the v a lv e , thus le a v in g a s p a c e b etw e e n the la m in a and the s h e ll w a ll. In n e ith e r v a lv e is th e r e a m e d ia n se p tu m . A ty p ic a l s p e c i m e n is 8 m m lon g, 4 .5 m m w id e and 3.0 m m th ick . A g e r o n tic fo r m is 7.5 m m lon g, 5.5 m m w id e and 5.5 m m th ick . D is cu s s io n . - - Cr a n aen a in th is c o lle c t io n a re so m e w h a t s m a lle r than ty p ic a l m e m b e r s of the g en u s. It is a s s u m e d that th e s e s h e lls a r e m a tu r e , h o w e v e r , fo r th e r e a re s p e c im e n s that sh ow g e r o n tic c h a r a c t e r i s t i c s su c h as cr o w d in g of grow th lin e s alon g the a n te r io r m a r g in and in c r e a s e d g ib b o sity of the v a lv e s . C ran aen a has h ith e r to b e e n c o n s id e r e d to be a M is s is s ip p ia n gen u s although it had an a b so lu te range of m id d le D evon ian to M i s s i s sip p ian . The p e r fo r a te hin ge p la te in t h e s e P e n n sy lv a n ia n s p e c im e n s p la c e s th em u n m ista k a b ly in that g en u s. C ra n a en a m in u ta is d is t in gu ish ed fro m a ll e a r l ie r s p e c ie s by its m u ch s m a lle r s iz e and the len g th of the b ra ch id iu m w h ich in e a r l ie r s p e c ie s d o es not r e a c h the m id d le of the v a lv e . L o c a lity . - - 309. F a m ily C E N T R O N E L L ID A E Genus R H Y N C H O PO R A King, 1865 D ia g n o s is . - - S h e lls a r e p u nctate and r h y n c h o n e llifo r m and s u b p en tagon al in sh a p e. S h ell is c h a r a c te r iz e d by e x tr e m e fo ld and s u lc u s at the a n te r io r and the m a r k e d p lic a tio n s of e a c h v a lv e . A n te r io r end is bluntly tru n ca te, and the a n te r io r p o rtio n of the p e d ic le v a lv e is g e n tic u - la te , fo r m in g the d eep s u lc u s that c o r r e s p o n d s to the b r a c h ia l fold . RHYNCHOPORA MAGNICOSTA M ather, 1915 PI. 4, fig s . 12-14 1915. R hynchopora m a g n ic o sta M ather, B ull. Sci. Lab. D en iso n Univ. XVIII, p. 176, pi. X, fig s . 1 1 - l l c . D e s c r ip tio n . - - S h ells are subpentagonally shaped; p o s te r o la t e r al m a rg in s are a lm o st straight; a n te r o la te r a l m a rg in s are b road ly rounded. The a n terio r is tru n ca te. G r ea test width is at about the a n te r io r third of the sh ell. The width is so m ew h a t g r e a te r than the length. P e d ic le va lv e is gently co n v ex in the um bonal reg io n , b e c o m in g flat tow ard the m id -s e c tio n . The la te r a l p o rtio n s of the a n terio r th ird of th is valve a re som ew h at h ig h er than the m id -p o rtio n . It is th is e l e v a tion of the sid e s rath er than an actual d e p r e s s io n of the m id d le that fo r m s the s u lc u s. At the a n terio r m a rg in , the v a lv e is sh a rp ly g e n ic u late at 90° or m o r e , form in g a tongue w hich p rotru d es into the d o r sa l fold. In the p e d icle su lcu s th ere are four c o a r s e , flatten ed p lic a tio n s in the sp a ce of 8 m m and s ix on ea ch of the la te r a l s lo p e s . The b ra ch ia l valve has th ree p lic a tio n s in the sp a ce of 5 m m on the fold. E ach of the la te r a l slo p e s b e a r s six or se v e n p lic a t io n s . The length of one s p e c im e n from the E ly lim e s to n e is 13 m m , the w idth 14 m m and the th ic k n e ss is 9.5 m m . The s u r fa c e s of both v a lv e s are c o a r s e ly punctate. L o c a lity . - - 31 3. 43 S u b o rd er R H Y N C H O N E L L IN A S u p e r fa m ily R H Y N C H O N E L L IC A E F a m ily C A M A R O T O E C H IID A E G enus W E L L E R E L L A D unbar and C ondra, 1932 D ia g n o s is . - - S m a ll r h y n c h o n e llid s w ith sm o o th u m b o n e s. The p e d ic le v a lv e d e v e lo p s a d eep , sin u s alon g the a n te r io r th ir d of the s h e ll, w h e r e a s the b r a c h ia l v a lv e is m o r e o r l e s s u n ifo r m ly c o n v e x . P l i c a tio n s c h a r a c t e r iz e the c o m m is s u r e , and c o s t a e m a y a r i s e on th e a n t e r io r m a r g in s and a p p r o a c h the u m b one s. W E L L E R E L L A sp. P I. 2, f ig s . 2 1 - 2 4 D i s c u s s i o n . - - S e v e r a l s m a ll s h e lls r e s e m b lin g W e lle r e lla a r e p r e s e n t in the c o lle c t io n s fr o m the E ly li m e s t o n e . T h e s e a r e e x c e e d in g ly s m a ll, few in n u m b e r and quite v a r ia b le in fo r m . The s h e lls a v e r a g e 5.2 m m in w idth, 5.0 m m in le n g th and 3.1 m m in th ic k n e s s . A ll h a v e p lic a te a n te r io r c o m m i s s u r e s . It is im p o s s ib le to d e te r m in e fr o m e v id e n c e at hand w h e th e r t h e s e f o r m s a r e ju v e n ile or w h e th e r th e y r e p r e s e n t s m a ll, m a tu r e in d iv id u a ls. L o c a lit y . - - 309. S u b o rd er ST R O P H O M E N IN A S u p e r fa m ily ST R O P H O M E N IC A E F a m ily ST R O P H O M E N ID A E G enus D E R B Y IA W aagen, 1884 (e m e n d . G irty, 1908) D ia g n o s is . - - P la n o - c o n v e x , b ic o n v e x or c o n c a v o - c o n v e x s t r o - p h o m e n id s in w h ic h the p e d ic le v a lv e is a lw a y s l e s s c o n v e x th an the 44 b rach ial v a lv e . The angle fo r m e d by the lin e of c o m m is s u r e and the p e d icle in te r a r e a is alw ays g r e a te r than 90 d e g r e e s . The b ra ch ia l in te r a r e a is u su a lly o b so le te . T h ere is a stro n g m ed ia n sep tum , no spondylium , and th ere a re no dental la m e lla e . DERBYIA aff. D. HAESITANS Dunbar and Condra, 1932 PI. 2, fig s . 2 6 -2 7 D e s c r ip tio n . - -S h e ll is la r g e , h in g e -lin e stra ig h t, g r e a te s t width at or n ear the hinge lin e . C ardinal e x tr e m itie s are som ew h at rounded, although e a r lie r grow th sta g e s ap pear to be quite rounded. In terarea fo r m s an angle of about 100 d e g r e e s w ith the lin e of c o m m is su re and has an ap ical angle of 160 d e g r e e s . The p e r id e ltid a l a r e a is fain tly v is ib le on so m e s p e c im e n s and a p p ears to fo rm an angle of about 90 d e g r e e s . A d eltid al p late c o v e r s the d elth y riu m w hich has an ap ical angle of 40 d e g r e e s. The p e d ic le va lv e is a lm o st flat, but so m e s p e c im e n s exh ib it a v en tra l cu rvatu re along the a n terio r m a rg in , p roducing a so m ew h a t con cave v a lv e . The beak is v e r y low and in co n sp icu o u s. L ir a e are high, sh arp rid g es sep a r a te d by so m ew h a t w id er, fla tten ed s tr ia e , and they in c r e a s e by in terc a la tio n . Thus, e v e r y th ird or fourth lir a is stro n g er than the in terven in g o n es. In a m a tu re s p e c im e n th ere are about 20 lir a tio n s p er c e n tim e te r . The b ra ch ia l v a lv e is u n ifo rm ly c o n v e x lon gitu d in ally. T r a n s v e r s e ly the um bonal slo p e s tap er off ra th er sh a rp ly , fo rm in g a faint e a r -lik e p latform . The um bo is thus ra th er gibbous. C on cen tric growth lin e s in terrupt the lir a e at ir r e g u la r in te r v a ls a c r o s s the p e d i cle valve and a re m o r e p ro m in en t than th o se on the b ra ch ia l v a lv e . 45 In te r n a lly the p e d ic le v a lv e b e a r s a h ig h m e d ia n s e p tu m w h ic h e x te n d s fr o m the a p e x of th e d e lth y r iu m a p p r o x im a te ly o n e - t h ir d the le n g th of th e s h e ll. T he h ig h e s t p o in t of the s e p tu m is ju s t a n te r io r to th e d e lth y r iu m . F r o m th is p o in t it t a p e r s off s lo w ly . D im e n s io n s of a ty p ic a l s p e c im e n a r e a s fo llo w s : le n g th 5 .4 c m , w id th 8.1 c m , th ic k n e s s 2. 3 c m . D is c u s s io n . - - T h is s p e c i e s of D e r b y ia is c l o s e l y a llie d to D. h a e s it a n s D unbar and C o n d ra p a r t ic u la r ly in sh a p e and o u tlin e . H o w e v e r , it m a y b e d is t in g u is h e d fr o m the la tte r by the n a tu r e of its s u r fa c e o r n a m e n ta tio n . T h e s u r f a c e of D. h a e s it a n s is m a r k e d b y rou n d ed , r a d ia l l i r a e w h ic h a r e s e p a r a t e d b y n a r r o w e r s t r ia e , w h e r e a s the li r a e of th is D e r b y ia a r e n a r r o w and r i d g e - l ik e and a r e s e p a r a te d by w id e r , fla tte n e d a r e a s . L o c a l i t y . - - 309. F a m i ly C H O N E T ID A E ' G enu s C H O N E T IN A K ro to w 1888 C H O N E T IN A F L E M IN G I (N o rw o o d and P r a tte n , 1854) P I. 2, fig . 25 ' 1854. C h o n e te s f le m i n g i N o r w o o d and P r a tte n , Jou r. A ca d . N at. S ci. P h ila ., v o l. 3, p. 26, p i. 2, fig . 5 a - e . One p e d ic le v a lv e of a C h o n etin a is p r e s e n t in the c o lle c t io n s of the E ly fau n a. The v a lv e is r a d ia lly s t r ia t e w ith a n a r r o w , d e e p ly in c is e d s in u s . L o c a l it y . - - 328. 46 S u p e r fa m ily PR O D U C TIC A E F a m ily P R O D U C T ID A E G enus DIAPHRAGM US G irty, 1911 D ia g n o s is . - -P r o d u c tid s w ith a s m a ll v is c e r a l a r e a and g r e a tly elo n g a ted tr a il. A d iap h ragm a r i s e s fr o m the b r a c h ia l v a lv e and e x tends to the p e d ic le v a lv e , thus se p a r a tin g the v is c e r a l a r e a fro m the tr a il. E lia s (1957, p. 505) l i s t s tw o p r in c ip a l c h a r a c t e r is t ic s that d if fe r e n tia te th is genus fr o m P r o d u c tu s : the la r g e r diap h ragm w h ich m a y r be tr ip a r tite , and the sh o r te r len gth of th e /tr a il. D IAPH RAGM US cf. D. F A SC IC U L A T U S (M cC h esn ey, 1860) P L 3, f ig s . 9-11 1860. P ro d u ctu s fa s c ic u la tu s M cC h esn ey , D e s c r ip tio n s of new s p e c ie s of f o s s i l s fr o m the P a le o z o ic r o c k s of the w e s te r n U nited S ta tes. D isc u s s io n . - - Two s p e c im e n s are r e fe r r e d to D iap h ragm u s on the b a s is of the w id e d iap h ragm and to D. fa s c ic u la tu s on the b a s is of the le n g th -w id th ra tio of the v is c e r a l d is c . In D. fa s c ic u la tu s the v i s c e r a l d isc is about one and o n e -th ir d t im e s w id e r than it is lon g. D ia p h ragm u s is u s u a lly thought of as a M is s is s ip p ia n gen u s. H o w ev er , it a ls o o c c u r s in undoubted P e n n sy lv a n ia n ro c k s in N evada. L o c a lity . — 31Z, 323. G enus D1CTYOCLOSTUS M u ir-W ood , 1930 D ia g n o sis . - - C o sta te p ro d u ctid s w ith r e tic u la te u m b o n es, and w ith con vex, g en ic u la te p e d ic le v a lv e s w ith e r e c t s p in e s . The b r a c h ia l va lv e is m o d e r a te ly c o n ca v e and w ithout s p in e s . T h ere is no m a r g in a l 47 d ia p h ra g m arou n d the v i s c e r a l d is c , and the s h e lls la c k te e th and s o c k e ts . D IC T Y O C L O ST U S A M E R IC A N U S D unbar and C ond ra, 1932 P I. 3, fig . 15 1932. P ie t y o c lo s t u s a m e r ic a n u s D unbar and C ond ra, N e b r a s k a G eo l. S u rv. B u ll. N o. 5, 2nd S e r ., p. 218, p i. 34, f ig s . 3 -6 . D e s c r ip t io n .- -S h e ll is su b q u a d ra te, le n g th about eq u a l to w id th . H in g e -lin e str a ig h t, s lig h tly l e s s than the g r e a t e s t w id th . P e d ic le v a lv e c o n v e x r e g u la r ly a c r o s s p o s t e r io r h a lf of the s h e ll. A v a g u e m e d ia n s u lc u s is e v id e n t fr o m the m id d le of th e v i s c e r a l d is c to the a n te r io r m a r g in of the t r a il. On the tr a il, the s u lc u s is b ro a d and s h a llo w . F in e c o s ta e c o v e r the s u r fa c e , the p o s t e r io r t w o -th ir d s of w h ic h is m a r k e d -b y c o n c e n tr ic ru g a e w h o s e s tr e n g th is eq u a l to that of the c o s t a e . The r e s u ltin g r e tic u la tio n s a p p ea r as u n ifo rm s q u a r e s . T he e a r s a r e of m o d e r a te s iz e and a r e not s h a r p ly d e lin e a te d fr o m the u m b o n a l s lo p e s . R e tic u la tio n s ex te n d o v e r the e a r s . M inute s p in e s a r e d is tr ib u te d i r r e g u la r ly o v e r the s u r fa c e , alth ou gh th ey a r e c o a r s e r on the e a r s and s l o p e s . L o c a lit y .- - 327. G enus A N T IQ U A T O N IA M ilo r a d o v ic h , 1945 D ia g n o s is . - - S e m ir e t ic u la t e p r o d u c tid s c h a r a c t e r iz e d by a p r e - a u ra l r id g e on e ith e r s id e of the u m b o of the p e d ic le v a lv e . T h is r id g e is the e x te r n a l e x p r e s s io n of a v e r t i c a l p a r titio n w h ic h s e p a r a t e s the v i s c e r a l c a v ity fr o m e a r s . S p in es alon g th is r id g e a r e a r r a n g e d in a s in g le row and in c r e a s e in s iz e to w a r d the la t e r a l s lo p e s . P i s c u s s i o n . - - G irty (1935, p. 7) p o in ted out and d e s c r ib e d the 48 rid g e and row of s p in e s b etw een the e a r s and u m b o n e s of s o m e p r o d u c - tid s he had d e s c r ib e d e a r lie r , m en tio n in g s p e c if ic a lly P r o d u c tu s h e r m o - sa n u s and P . c o l o r a d e n s i s . A t the tim e , G irty a p p a ren tly did not c o n s id e r th e s e fe a tu r e s of g e n e r ic or e v e n s p e c ific v a lu e , fo r the sta tu s of the two m e n tio n e d s p e c ie s r e m a in e d u n ch anged. M ilo r a d o v ic h (1945, p. 496) se p a r a te d the gen u s A n tiq uaton ia fr o m the genus D ic ty o c lo stu s on the b a s is of the p r e - a u r a l c r e s t s d e s c r ib e d by G irty. The c r e s t s and sp in e s a r e w e ll d is p la y e d on s e v e r a l of the E ly A n tiq u a to n ia . A N TIQ U A TO N IA H ER M O SA N A (G irty, 1903) P I. 3, f ig s . 5 -8 1903. P r o d u c tu s s e m ir e tic u la tu s v a r . h e r m o s a n u s G irty, U-. S. G eol. Surv. P r o f. P a p e r 16, p. 358, pi. II, f ig s . 1 -4 . D e s c r ip tio n . - - S h e ll is su b q u ad rate in o u tlin e. P e d ic le v a lv e is gibb ou s and g e n ic u la te . A s u lc u s b e g in s a n te r io r to the b ea k as a broad, g en tle d e p r e s s io n and co n tin u es to w a rd the fro n t in c r e a s in g only slig h tly in depth. The s u lc u s is m o s t p ro n o u n c ed on the a n te r io r slo p e , b e c o m in g o b s o le s c e n t both at the b ea k and a lo n g the a n te r io r m a r g in . C o sta e a r e s m a ll and rounded on the v i s c e r a l d is c and a r e u n ifo r m ly c r o s s e d by c o n c e n tr ic ru g a e at in te r v a ls about tw ic e the d ista n c e of the c o s ta e , thus p ro d u cin g m o r e or l e s s r e c ta n g u la r r e tic u la tio n s . On the v is c e r a l d is c c o s ta e in c r e a s e by b ifu rca tio n . On the a n te r io r slo p e , the c o s ta e in c r e a s e g r e a tly in str e n g th and in s o m e c a s e s c o a l e s c e . The e a r s a r e m o d e r a te ly la r g e , and a re bluntly rounded to s o m e w h a t m u c r o n a te . B eg in n in g ju st a n te r io r to the b eak and above the a u r ic u la tio n s, th e r e is a s in g le row of s p in e s along a r a is e d c o sta tio n , the cu r v a tu r e of w h ich p a r a lle ls that of the v is c e r a l 49 p o rtio n of the p e d ic le v a lv e . The p o s te r io r sp in e s a re s m a ll and rath er c lo s e to g eth er, but s p in e s a re c o a r s e r and m o r e w id e ly se p a r a te d t o w a rd the a n te r io r . S p in es e ls e w h e r e about the s h e ll a re c o a r s e and i r r e g u la r ly sp a ced . The s p in e s do not ap p ear to a ffe c t the p a tte r n of the su r fa c e m a r k in g s . A ty p ic a l s p e c im e n is 3.6 cm w id e , 2 .9 cm lon g and 2.0 cm thick. This s p e c ie s is co m m o n in the E ly lim e s to n e , p a r tic u la r ly in the lo w e r p art of the se q u e n c e . L o c a lity . - - 314. A N TIQ U A TO N IA E L Y E N SIS n. sp. PI. 3, f ig s . 1 2 -1 4 PI. 4, f ig s . 8 -11 D e s c r ip tio n . - - S h ell is su bq u ad rate lo n g itu d in a lly . B eak is sm a ll; h in g e -lin e is s tr a ig h t. P e d ic le v a lv e is gibb ou s, co n v ex , g e n ic u la te. A m ed ia n s u lc u s b e g in s on the v is c e r a l d is c as a v a g u e, sh a llo w d e p r e s s io n and co n tin u es down the a n te r io r slo p e w h e r e it is m o r e d eep ly sin u ate in s o m e s p e c im e n s than in o th e r s . Low rounded c o s ta e are c r o s s e d by c o n c e n tr ic ru gae on the v is c e r a l d isc; on the s lo p e s , the co sta e in c r e a s e by in te r c a la tio n . E igh t to te n c o s ta e o c c u r in the sp a ce of 1 cm , and th eir w idth is about eq u al to the sp a c e se p a r a tin g th em . The su r fa c e is m a rk ed by n u m ero u s s le n d e r sp in e s d is tr ib u te d m o r e or l e s s r e g u la r ly o v er the su r fa c e . A sin g le row of p r e - a u r a l sp in e s runs fro m the beak along the a n t e r o - la t e r a l m a r g in . T h e r e is a rid ge p a r a l le l to th is row of s p in e s as in A ntiquaton ia h e r m o s a n a . The b r a c h ia l v a lv e is m o d e r a te ly c o n c a v e , b ein g a lm o s t flat a c r o s s the v is c e r a l d is c , and in s o m e s h e lls th ere is a slig h t fold 50 c o r r e s p o n d in g to the su lc u s of the p e d ic le v a lv e . The v i s c e r a l d is c is r e tic u la te and w ith o u t v is ib le s p in e s . In tern a lly , the b r a c h ia l v a lv e sh o w s a str o n g c a r d in a l p r o c e s s fr o m w h ic h tw o s h o r t r id g e s p ro tru d e la t e r a lly . T h e r e is no m e d ia n sep tu m . A ty p ic a l s p e c im e n is 2.2 cm in w idth, 2 .4 cm in le n g th and 1.2 cm in th ic k n e s s . P is c u s sio n . - - A n tiq u a to n ia e ly e n s is d iffe r s fr o m A n tiq u aton ia he rm os ana (G irty) in that the f o r m e r is m u ch s m a lle r than A. h e r m o - sa n a ; fr o m A. m o r r o w e n s is (M ath er) in that A. e l y e n s i s is c o s ta te w h e r e a s A. m o r r o w e n s is is lir a t e . L o c a lit y . - - 314, 309. S u b fa m ily M A R G IN IFE R IN A E G enus LISSO M A R G IN IFE R A n. gen. D ia g n o sis^ .--F a in tly o r n a m e n te d M a r g in ife r in a e c h a r a c te r iz e d by a p a ir of s p in e s on e a c h e a r , an o u ter c o a r s e sp in e d ir e c te d p o s t e r i o r ly in lin e w ith the la t e r a l m a r g in of the e a r , and a v e r y sh o rt s le n d e r inner sp in e h a lf the d is ta n c e fr o m the b ea k to the tip of the e a r . O th e r w is e , the s u r fa c e is c o m m o n ly d ev o id of o r n a m e n ta tio n . F a in t rugae m a y be s e e n on the v i s c e r a l d is c s of s o m e s p e c im e n s , and d is c e r n ib le s tr ia e a r e a ls o o c c a s io n a lly p r e s e n t, but th e y a r e not c h a r a c t e r is t ic . The s u r fa c e is m a r k e d by only a few c o a r s e s p in e s , u s u a lly w ith one on e ith e r u m b on al s lo p e and fou r to s ix s c a t t e r e d ir r e g u la r ly about the m e s ia l p o r tio n of the p e d ic le t r a il. The b r a c h ia l v a lv e is w ith ou t spin es. The c a r d in a l p r o c e s s is ra th e r s h o r t and stou t, w ith th r e e lo b es p r o je c tin g p o s te r io r ly , the c e n tr a l lo b e b ein g the lo n g e r . M u sc le s c a r s of the b r a c h ia l v a lv e a r e e le v a te d , fla b e lla te p la tfo r m s se p a r a te d by a 51 low m ed ia n rid ge w h ich a r i s e s ju st a n te r io r to the b a s e of the ca rd in a l p r o c e s s and co n tin u es fo rw a rd h alf the d ista n c e of the v is c e r a l d is c . A n te r io r and la te r a l to the m u s c le s c a r s a r e r e n ifo r m b r a c h ia l im p r e s s io n s . A long the a n te r io r m a r g in of the v is c e r a l d is c th e r e are s ix to eigh t s m a ll s p in e s w h ich w ould s e e m to a lly the gen u s to M a r g in ife r a . At the p o s te r o la te r a l m a r g in s of the d isc , th e r e a r e w r in k le s that c o r resp o n d to th o se of the v e n tr a l v a lv e and m a y h ave fa c ilita te d a r tic u la tion. The p e d ic le in te r io r is ty p ic a lly sm o o th w ith on ly fain t d id u c- tor s c a r s . A dductor s c a r s a re on a p ro m in en t p la tfo rm that is r a is e d w e ll above the flo o r of the v a lv e . T h is p la tfo rm ex ten d s about h alfw ay a c r o s s the v a lv e and is bluntly rounded at the a n te r io r end. The p o s t e r io r end of the adductor m u s c le p la tfo rm ta p e r s n a r r o w ly and d oes not r e a c h to the h in g e -lin e of the sh e ll. G en otyp e. - - L is s o m a r g in if e r a nuda n. sp. D isc u s s io n . - - T his gen us c l o s e l y r e s e m b le s M a r g in ife r a W aagen, p a r tic u la r ly in the m a r g in a l fla n g e of the b r a c h ia l v a lv e that c h a r a c te r iz e s both s h e lls . H ow ever, th is genus d iffe r s fro m M a r g in i fe r a in its d is p o s itio n of s p in e s and its ty p ic a lly sm o o th su r fa c e . LISSO M A RG IN IFER A N U D A n. sp. PI. 4, f i g s . 1 -7 D e s c r ip tio n . - - S h ell is e v e n ly rounded in outline a n te r io r to the h in g e -lin e . G r e a te st w idth is at the h in g e -lin e , and the s h e ll is w id er than it is lon g. E a r s a r e d is tin c t fro m the um bonal slo p e and a re angu la r to a lm o st m u c r o n a te . The p e d ic le v a lv e is str o n g ly co n v ex , and the 52 c u r v a tu r e is g e n ic u la te . T he s u r f a c e of b oth v a lv e s is t y p ic a lly d e v o id of p r o m in e n t o r n a m e n ta tio n , a lth o u g h fa in t s t r ia e and r u g a e a r e p r e s e n t . S o m e s p e c im e n s w ith th e s p in e s s t ill in ta c t e x h ib it a c o m p le t e ly s m o o th s u r f a c e , and th e p r e s e n c e of th e s p in e s p r e c lu d e s e r o s io n of the c o s t a e . F r o m e a c h of th e e a r s , tw o s p in e s a r i s e . A n o u te r , c o a r s e sp in e is d ir e c t e d p o s t e r i o r l y in th e s a m e p la n e as th e la t e r a l m a r g in of th e e a r . A n in n e r , s m a l l e r s p in e , q u ite s h o r t and s le n d e r , is h a lf the d is t a n c e f r o m the b e a k to th e tip of the e a r , and is d ir e c t e d d o r s a lly . T he b r a c h ia l v a lv e is m o d e r a t e l y c o n c a v e e x c e p t fo r the m a r gin w h ic h is p r o d u c e d by c r o w d e d g r o w th lin e s w h ic h fo r m a s h e l f - l i k e m a r g in . T he w id th of th is m a r g in a l s h e lf is about 1/4 th e le n g th of th e b r a c h ia l v a lv e , and it e x te n d s a lo n g the l a t e r a l m a r g in s a lm o s t to the h in g e - li n e . In te r n a lly , th e f e a t u r e s of the b r a c h ia l v a lv e a r e d is t in c t iv e . B e g in n in g at th e c a r d in a l p r o c e s s , a f la n g e - l ik e r id g e e x te n d s a ro u n d th e p e r ip h e r y , and th e p o s t e r i o r m a r g in of th is m a r g in a l fla n g e is c r e n u la te . T h e m e d ia n s e p tu m is q u ite lo w in the p o s t e r io r p o r tio n of the s h e ll, b e c o m in g h ig h at the a n te r io r m a r g in of the v i s c e r a l d is c . At the a n t e r io r m a r g in of th e v i s c e r a l d is c , t h e r e is a row of fr o m e ig h t to te n c o a r s e , s h o r t s p in e s . T h e s e s p in e s a r e a r r a n g e d in an a r c in fr o n t of e a c h b r a c h ia l i m p r e s s io n . A t y p i c a l s p e c im e n is 2.1 c m in w id th , 1.4 cm in le n g th and 1.1 c m in t h ic k n e s s . D is c u s s io n . - - L is s o m a r g in if e r a d if f e r s fr o m K o z lo w s k ia s p le n d e n s (N o rw o o d and P r a tte n ) in th at L . nuda la c k s a s u lc u s and e s s e n t ia ll y la c k s s u r f a c e o r n a m e n ta tio n . It a ls o h a s a h ig h m e d ia n s e p tu m th at r e a c h e s th e a n te r io r e d g e of th e v i s c e r a l d is c , w h e r e a s K. 53 splendens has a low m edian septum that does not reach the m argin of the v is c e r a l disc. L o cality. - -309. Genus LINOPRODUCTUS Choa, 1927 Diagnos i s . - - Lirate productids with strongly convex pedicle valves and concave brachial v a lv e s. The sh ells are thin and are o rn a m ented with e r e c t spines and radiating lirae; sh ells lack concentric ru gae and consequently the resulting reticulations. A tripartite cardinal p r o c e s s is ch a ra cte ristic of the genus. LINOPRODUCTUS MAGNISPINUS Dunbar and Condra, 1932 PL 3, fig. 2 1932. Linoproductus m agnispinus Dunbar and Condra, N ebraska Geol. Surv. Bull. 5, 2nd S eries, p. 244, pi. XXVII, figs. 6-8. D escrip tion . - - Shell is elongate with g rea test width along hinge- line. P ed icle valve is geniculate and its beak is incurved. Shell is thin and ornam ented with num erous liration s. In a typical shell, there are sev en or eight lirations in the space of 5 m m a c r o s s the m iddle of the pedicle valve. A few stout spines are sca ttered over the surface with one or two in the center of a slight m e s ia l sulcu s. F ive or six spines are on each ear and are s m a lle r than the body spines. The b a ses of the spines are form ed at the an astom osing of three or four lirations, which separate on the anterior side of the spine. E ars are of m oderate size and are som ew hat angular. Four or five w rin kles appear on each ear but fade away on the anterolateral slop es. The brachial valve is som ew hat concave, although the v is c e r a l 54 d is c is rath er flat. At the tr a il the v a lv e is sh a r p ly g en ic u la te. A ty p ica l s p e c im e n is 3.8 m m in w idth and 4.6 m m in length. L o c a lity . - - 31 6. LIN O PR O D U C TU S P R A T T E N IA N U S (N orw ood and P ra tte n , 1855) PI. 3, fig. 1 1855. P ro d u ctu s p ratten ian u s N orw ood and P ra tte n , Jour. A cad . Nat. Sci. P h ila ., v o l. Ill, p. 17, pi. 1, fig s . lO a-d. D e s c r ip tio n . - -S h e ll is su boval in outline. P e d ic le v a lv e is u n i fo r m ly co n v e x and a lm o s t h e m is p h e r ic a l. G r e a te s t w idth is at the h in g e -lin e . Shell is g en ic u la te at the tr a il. A ty p ic a l s p e c im e n is 4.8 cm w id e. Low, rounded c o s ta e rad iate fr o m the b e a k and in c r e a s e by in te r c a la tio n a c r o s s the v a lv e . C o sta e a ls o in c r e a s e in c o a r s e n e s s t o w a rd the a n terio r slo p e. In the u m b on al r e g io n ten or e l e v e n c o s ta e o c cupy a sp a c e of 5 m m , w h e r e a s s e v e n or eig h t occu p y the s a m e s p a c e a c r o s s the v i s c e r a l p o rtio n of tl. p e d ic le v a lv e . Spines are c o a r s e and e r e c t and u n ifo r m ly d is p o s e d o v e r the p e d ic le v a lv e in a q u in cu axial p a ttern . T h ir ty -tw o sp in e s a r e p r e s e n t on the v i s c e r a l p ortion of a s h e ll 4.8 cm w id e. Spine b a s e s m a y be fo r m e d fr o m one or m o r e (u su a lly two or th r e e ) c o s t a e . T h e s e c o s ta e se p a r a te on the a n te r io r ed ge of the spine b a s e . Internally the adductor m u s c le s c a r s are c l o s e l y sp a c e d , being se p a r a te d only by a low m e d ia n ridge. The d id u ctors a r e w id e ly s e p a rated and so m e w h a t te a r - s h a p e d , the attenu ated p o rtio n b ein g d ir e c te d tow ard the c en ter of the v a lv e . L o c a lity . - - 309. Suborder SPIRIFERIN A Super fa m ily SPIR IFE R IC A E F a m ily SPIRIFERID AE Subfam ily SPIR IFE R IN A E Genus SPIR IFE R Sow erby, 1815 D ia g n o s is .- -S h e lls a re u su a lly t r a n s fe r s e with sim p le p lic a tions over the en tire su rfa ce of both v a lv e s . The p ed icle v a lv e is h igh er than the b rach ial va lv e. U su ally a p rom in en t su lcu s is p r e s e n t on the p ed icle va lv e, and a co rresp o n d in g fold is p r e s e n t on the b rach ial valve. The beak of the b rach ial is l e s s prom in en t than that of the p e d i cle valve. SPIR IFE R OCCIDUUS Sadlick, I960 PI. 5, fig s. 3-7 I960. S pirifer occiduus Sadlick, Jour. P aleon tology, v. 34, no. 6, p. 1210-1214. De s c r iption. - - She 11 is s p ir ife r o id in shape, the width being a little g r e a te r than the length, and the g r e a te s t width is at the h in g e -lin e . A sh ell of av era g e s iz e has the follow ing d im en sion s: width, 4.2 cm; length, 2.7 cm . The cardinal e x tr e m itie s m a y be sligh tly m ucronate, but they are u sually so m ew h a t rounded. E le v en to th irteen subangular p lication s m a r k the slo p e s of the ped icle va lv e. At the umbo, the ribs a re sim p le, but as they begin to expand, they bifurcate and continue over the su rface as sim p le p lic a tions. The su lcu s contains th ree to five ribs of w hich the m ed ia l one is co m m o n ly rather prom in en t. The beak is sligh tly incurved. B rachial fold is w ell defined, u su ally having fro m four to s ix p lica tio n s. 56 Short, stout dental la m e lla e support the te e th of the p e d ic le v a lv e but do not exten d out onto the flo o r of the v a lv e . A dductor m u s c le s c a r s a re d e e p ly in c ise d , and the s c a r it s e lf is u s u a lly sa g g ita te in sh ape. T h is a r e a is bounded by rounded, a lm o s t fla b e lla te diductor s c a r s . The v a lv e is w ithout a m e d ia n sep tu m . Incipient d eltidal p la te s b o r d e r the d elth y riu m w h ich f o r m s a high, n a r r o w tr ia n g le . In te r a r e a is b road and flat, the p a lin tro p e of w hich is s e r r a t e . The s p a c e b en eath the in te r a r e a of the p e d ic le v a lv e is u su a lly m u c h th ick en ed . B r a c h ia l in te r io r s are s im p le w ithout m e d ia n sep ta. T h ere is a thin in te r a r e a w h ic h is c le ft by a b ro a d n ototh yriu m . The la tter is bounded by sh o r t b r a c h io p h o r e s . Locality. - -320,321. G enus N E O S P IR IF E R F r e d e r i c k s , 1919 D iagn os i s . - -S p ir ife r o id s h e lls w ith f a s c ic u la te r ib s . S h ells are w id e r than long w ith the g r e a te s t w idth at or n e a r the h in g e - lin e . E x t r e m it ie s v a r y fr o m rounded to m u c r o n a te . H in g e -lin e is straigh t, in te r a r e a is a low , broad tr ia n g le . P e d i c le v a lv e is m a r k e d by a deep, angular s u lc u s w h ich c o r r e s p o n d s to the b r a c h ia l fold. Both v a lv e s are ribbed w ith unequal p lic a tio n s that are grou p ed into f a s c i c l e s . T h e s e p lic a tio n s m a y b ifu rca te r e p e a te d ly or fa s c ic u la tio n m a y only be e v i dent in the um b onal a r e a . N E O S P IR IF E R T R IP L IC A T U S (Hall, 1852) 1852. S p ir ife r t r ip lic a tus Hall, S ta n sb u ry 's E x p ed itio n to the G reat Salt L ake, Append. E, p. 410. 57 D e s c r ip tio n . - -S h ell is of m ed iu m s iz e , ty p ica lly about 5 to 7 cm in width and 4 to 5 cm in length. Outline is subtriangular, and card in al e x tr e m itie s are sh a rp ly defined. A n arrow su lcu s bounded by two d istin ct ribs begin s at the um bo and fans out into a broad sh allow d e p r e s s io n on the a n terio r slo p e. The ribs bifurcate ju st a n terio r to the um bo and in c r e a s e th e r e a fte r by b ifurcation. Tow ard the a n terior, the f a s c i c l e s u su a lly c o n s is t of th ree subrounded ribs w hich a r e unequal in s iz e . T h ere are fro m ten to tw elv e f a s c i c l e s p r e s e n t on a m a tu r e sh ell. O rnam entation of the b ra ch ia l valve is s im ila r to that of the p e d ic le v a lv e ex ce p t that th ere a re c o m m o n ly one or two fe w e r f a s c i c le s on the b ra ch ia l v alve. L o c a lity . - - 309, 327. S ubfam ily A M BO C O ELIIN AE G eorge Genus CRURITHYRIS G eorge, 1931 D ia g n o s is . - - S m a l l p la n o -c o n v e x sh e lls w ith g r e a te s t w idth a n te r io r to h in g e -lin e . Width is u su a lly g r e a te r than length. P e d ic le v a lv e is gibbous and m a y have a sligh t sin u s. Beak is in cu rved but does not co v e r d elth yrium . In terarea is a high, n arrow tr ia n g le . B ra ch ia l v a lv e stra ig h t along p o s te r io r m a r g in and rounded a n terio r ly . The valve is u su a lly flat although it m a y be fain tly con cave to convex. CRURITHYRIS P L A N O C O N V E X A (Shumard, 1855) PI. 4, fig s . 34-3 5 1855. S p irife r p ia n o -c o n v e x a , Second Ann. Rept. M is s o u r i G eol. Surv., p. 202. 58 D escrip tio n . - -Shell is sm all, p lan o-con vex with the length and width about equal. P ed icle valve is quite convex, hin ge-lin e short and straight, being about fiv e-eig h th s of the g rea te st width of the shell. Beak is high and incurved. Interarea is a high, narrow triangle, the flat surface of w hich contrasts sharply with the rounded surface of the p o s tero la tera l m argin s. Delthyrium is high and narrow , and bounded on the sides by low flan ges. B rachial valve is variably concave, flat or convex. The surface of both va lv es appears granular. Dunbar and Con dra (1932, p. 345) state that th ese granules r e p r e se n t m inute spine b a s e s . D is c u s s io n . - - C. p lanoconvexa is rare in the Ely lim esto n e, only sev en sp ecim en s being found am ong m y ria d s m a ll sh ells. T hese crurithyrids are also som ew hat s m a lle r than those reco rd ed from other lo c a litie s. An average sp e c im e n m e a s u r e s 5 m m in width and 4.5 m m in height. L o ca lity . - - 309. Superfam ily ROSTROSPIRICAE F a m ily RHYNCHOSPIRINIDAE Genus HUSTEDLA Hall and Clark, 1893 D ia g n o s is .--S m a ll co stella te rhynchospirinid with short, straight h in ge-lin e and s m a ll triangular cardinal area on the pedicle valve refe rred to as a sym phytium . The genus strongly r e s e m b le s E u m etria ; how ever, Hustedia can be distinguished from that genus by its com p letely fused sym phytium , w h e rea s the sym phytium of E u m etria is cleft. H U ST E D IA R O T U N D A n. sp. PI. 4, f ig s . 4 2 -4 5 D e s c r ip tio n . - - S h ell su b -o v a te in outline, g r e a t e s t w idth ju st a n te r io r to m id d le p o rtio n of the sh e ll, g r e a t e s t th ic k n e s s ju st a n te r io r to b r a c h ia l beak. A n te r io r m a r g in s lig h tly tr u n c a te d in s o m e s p e c i m e n s , and a vague s u lc u s is p r e s e n t on s o m e p e d ic le v a lv e s . The s u r fa c e is m a r k e d by 20 to 24 c o s t e lla e w ith an a v e r a g e of 22. C o ste lla e a r e rounded, equal to the d e p r e s s io n s that s e p a r a te th em , and a re of u n iform s iz e in the c e n te r of the s h e ll, d e c r e a s i n g rap id ly in s iz e t o w a rd the p o s te r o la t e r a l m a r g in s . P e d ic le v a lv e m o r e c o n v e x to w a rd the beak. B eak s u b - e r e c t . F o r a m e n te r m in a l, s u b - c i r c u l a r . S ym p hytium s m a ll, tria n g u la r w ith the apex tru n ca ted by the fo r a m e n . P o s t e r i o r end is p a r a lle l w ith the line of c o m m i s s u r e . Intern ally m u s c l e s c a r s a r e not v is ib le , and th ere are no dental la m e lla e . The b r a c h ia l v a lv e is m o r e rounded in outline than the p e d ic le v a lv e , being a lm o s t oval and is s lig h tly l e s s con vex. In ternally a sh o rt m e d ia n sep tu m exten d s a n te r io r ly o n e -fo u r th the length of the v a lv e and su pp orts a to n g u e -lik e ca rd in a l p r o c e s s w h ich is r e c u r v e d into the p e d ic le v a lv e . Internally the s p ir a lia ap pear as c o m p r e s s e d c o n e s of eight volu tion s and the outer r im s are m a r k e d by n u m e r o u s m in u te s p in e s . The yoke is h igh ly o r n a m e n te d w ith sp in e s and a n tle r -lik e p r o c e s s e s . D im e n s io n s (in m m ) of s e v e n ty p ica l s h e lls a re as follow s: 60 Length Width T hicknes s No. of c o s te lla e 12.7 9.8 7.4 24 14.1 11.5 9.1 22 11.7 9.1 6.9 22 10.6 9.0 6.8 22 8.0 6.7 4.8 24 9.9 7.9 6.6 20 D is c u s s io n . - - W ell p r e s e r v e d s p e c im e n s of H ustedia rotunda are e a s ily distin gu ish ed from other P en n sy lv a n ia n s p e c ie s of that genus. H ustedia rotunda differs from H. m i s e r i M ather in that the latter has "about 20 . . . p lica tio n s," w h e r e a s H. rotunda has an a v era g e of 22. The c o s te lla e are c o a r s e and of equal stren gth in the central portion of the sh ell, d e c r e a sin g m a rk ed ly in s iz e tow ard the la te r a l m a r g in s . The m o s t strik in g c h a r a c te r is tic of this s p e c ie s , h ow ever, is the a lm o st c ircu la r outline of the b rach ial valve, sep aratin g it from any other s p e c ie s of H u sted ia, w hich c o n siste n tly have elongate outlines. Rounded c o sta e of H ustedia rotunda a ls o s e r v e to d istin gu ish it from H. m i s e r i w hich has m a rk ed ly angular co sta e. L o c a lity . - - 309. HUSTEDIA MISERI subsp. GIBBOSA n. subsp. PI. 4, fig s. 38-41 Des cr iption. - - Shell oval in outline, som ew hat incurved tow ard the beak. A nterior end and an tero la te ra l m a rg in s tend to be truncated cau sin g the oval outline in so m e s p e c im e n s to appear polygonal. A vague sulcus is p r e se n t on the p ed icle valve without a co rrespon d in g 61 fold on the brachial valve. Twenty to twenty-four rounded co stella e are presen t on both v a lv es. These co stella e are co a r se in the middle of each valve and d e c r e a se p r o g r e s s iv e ly in size toward the lateral m a r gins. The pedicle valve in c r e a se s in convexity toward the beak. Beak su b -e r e c t. F oram en term inal, subcircular. Symphytium sm all, subtriangular, p osterior portion slightly incurved toward the pedicle in terior. A nterior portion lie s in a plane with the line of c o m m is s u r e . Brachial valve is oval and slightly le s s convex than the pedicle valve. Internally this sp e c ie s r e s e m b le s Hustedia rotunda. P is c u s s io n . - - This sp e c ie s of Hustedia is distinguished from H. rotunda by its c o a r s e r costae, uniform d e c r e a se in siz e of costae t o ward lateral m argin and m ore nearly oval brachial valve; from H. m is e r i and H. m orm on i by its rounded and m o re num erous costae and gibbous nature of the valves. L o ca lity . - - 309. F am ily ATHYRIDAE Subfamily ATHYRINAE Genus CLEIOTHYRIDINA Buckman, 1906 D ia g n o sis. - - A sub-oval athyrid w hose surface is m arked with irregu larly spaced, concentric la m ella e, each of which is finely spinose on the anterior m argin. CLEIOTHYRIDINA ORBICULARIS (M cChesney, I860) PI. 4, figs. 36, 37 I860. Athyris orbicularis M cC hesney, D escr. New Species Pal. 62 F o s s ils , p. 47. 1932. C leiothyridina orbicularis (M cC hesney), Dunbar and Condra, N ebraska Geol. Surv. Bull. 5, 2nd Ser., p. 359, pi. XLII, figs. 1-4. Des cription . - -Sh ell is a lm o st equally biconvex, su b-oval in out line. A nterolateral and p o ste r o la te r a l m argin s tend to be som ew hat straight, how ever, causing outline to be slightly angular. G reatest width is just p o ste rio r to the m iddle of the shell; g rea te st th ick n ess is about in the center of the sh ell. A nterior m argin m a y be truncated, and a vague sulcus m ay be p resen t on the ped icle valve. P ed icle valve is m o re gibbous than the brachial valve. P e d ic le beak is incurved and e r e c t with a s m a ll circu lar fo ra m en at the tip. Deltidal plates are not seen, and palintrope is sm all. Surfaces of both valves are m ark ed with irreg u la rly spaced, concentric la m e lla e . The anterior m a rg in s of the la m e lla e are p r o duced into minute sp in es, causing w e ll p r e s e r v e d s p e c im e n s to appear a lm o st fuzzy. The la r g e s t sp e c im e n ob served in the co llection is 13.5 m m in length, 15.2 m m in width and 8.1 m m thick. Several sp ecim en s ap proach this siz e and som e fragm en ts indicate that definitely la r g e r sp ecim en s exist; how ever, the average length is som ew hat s m a lle r than 1 5 m m . L o ca lity . - - 309. Genus COMPOSITA Brown, 1849 Diagno s i s . - - Suboval to elongate athyrids, strongly biconvex with a sinuate anterior line of c o m m is s u r e . Beak of pedicle valve is 63 p rom in en t and m uch incurved; ped icle fo r a m e n is free and oval. Inter a rea is lacking. B rachial valve is sh orter than the p ed icle valve and the beak is l e s s prom inent. C oncentric growth lin es m a rk the su r fa c e s of both v a l v e s . COMP OS IT A A R G E N T E A (Shepard, 1838) PI. 4, figs. 31-33 1838. T erebratula arg en tea Shepard, A m . Jour. S ci., Vol. 34, p. 152, fig. 8. D e sc r ip tio n . - -S h ell sm a ll, suboval in outline, g r e a te st width about m id -r e g io n . Length ap p roxim ately equal to width. V alves are n early equally convex, with brachial valve being perhaps m o r e so. P e d ic le beak is low and incurved; in m any sh e lls the beak is only sligh tly m o r e prom inent than that of the brachial valve. The fo r a m e n is often ob scu re, but w hen p r e s e n t it is s m a ll and oval. T here is no in te r area. The su r fa c e s of both v a lv e s are c h a r a c te r iz e d by c lo s e ly spaced, co n cen tric growth lin es. The a n terior c o m m is s u r e is gently sinuate, reflectin g a shallow p ed icle su lcu s and an a lm o st obsolete b rach ial fold. D im en sion s of an av era g e s p e c im e n are as follow s: length, 16.5 mm; width, 16 mm; height, 17 mm; th ick n ess 11 m m . D iscu s s io n . - - This w r ite r follow s the argu m en ts of Dunbar and Condra in using the nam e C. a rgen tea to d istinguish sm a ll, su b c ircu la r c o m p o sita s. S hells of this d e scrip tio n occur co m m o n ly in the b asal Ely, and it is felt that the s p e c ie s can be d istinguished readily. L o c a lity . - - 31 3. 64 COMPOSITA SUBTILITA (Hall, 1852) PI. 5, fig. 8 1852. T erebratula subtilita Hall, Stansbury's Expl. and Surv. Great Salt Lake, p. 409, pi. IV, figs. la - 2 c . 1932. C om posita subtilita (Hall), Dunbar and Condra, N ebraska Geol. Surv. Bull. 5, 2nd S er., p. 363, pi. XLIII, figs. 7-13. D e sc r ip tio n . - -S h ell oval, g r e a te st width is anterior to the m id region of the shell, width is a lm o st tw o-th ird s of the length. P ed icle beak is prom inent, incurved and o b scu res the brachial beak. P ed icle valve b ears a deep sulcus at the anterior m a rg in w here it is a lm o st uni fo rm ly rounded. Toward the central part of the valve, the sulcus b e co m e s narrow and shallow and rem a in s so until it reach es the umbonal region. A n arrow fold begins near the beak of the brachial valve and continues a lm o st im p ercep tib ly a c r o s s the cen tral portion of the valve. Near the anterior m argin, the anterolateral m a rg in s sw eep down sharp ly toward the p edicle valve, thus form ing a v e r y prom inent fold just at the anterior m argin. The anterior of the sh ell is em arginate. Concentric growth lin es are ir reg u la rly spaced over the s u r face of both valves. An average s p ecim en has the following dim ensions: length, 27 mm; width, 25 mm; th ick n ess, 16 m m . L o c a lity . - - 31 3. Superfam ily PUNCTOSPIRICAE F a m ily SPIRIFERINIDAE Genus PU N CTO SPIR IFER North, 1920 65 Diagnos i s . - - Shell biconvex, w idest at or near the h inge-line, width is always greater than length. Cardinal ex trem ities range from rounded to alm ost m ucronate. Interarea is a low, broad triangle, lon gi tudinally concave. Beak is m od erately high and incurved. M esia l su l cus and fold are w ell developed; the corresponding c r e st and trough are flattened. The rem aining costae are rounded but tend to be angular to w ard the beak. Internally, the pedicle valve bears a high m edian septum and short, strong dental la m ella e. In the brachial valve the jugum is s le n der and V -shaped with its apex directed p o ste rio rly and into the pedicle v a lv e . PUNCTOSPIRIFER CAMPESTRIS (White, 1874) PI. 4, figs. 22-29 1874. Spiriferina spinosa var. ca m p estris White, Expl. and Surv. West 100 M erid., P r e lim . Rept. Invert. F o s s ., 21. 1877. Spiriferina octoplicata Sowerby, White, C. A., U. S. Geog. Surv. w est of the 100th M erid., vol. IV, Pal., p. 139, pi. X, figs. 8a- 8c. Diagnos is . - - Shell biconvex, greatest width at or near hinge- line, cardinal e x tr e m itie s m ay be either rounded or angular. Interarea is a low, broad triangle, longitudinally concave. P ed icle valve is m o re gibbous than the brachial valve. The beak is incurved, sm all and pointed. F rom the beak arise four sub rounded plications, the others arising indistinctly from either side of the beak. In a shell m easu rin g 27 m m wide and 18.8 m m long, twelve costae lie on either side of the sulcus. The floor of the sulcus is 66 d istin ctly flattened. The b ra ch ia l v a lv e is s m a lle r than the p e d ic le and is l e s s g ib bous. T here are s ix c o s ta e on eith er sid e of the m e s i a l fold. In v a r i ous m a tu re s p e c im e n s , this num ber v a r ie s fr o m five to six. The angu la r ity of the c o s ta e is in c o n s is te n t as w e ll, so that a gradation fro m rounded to angular m a y be seen . The su r fa c e of both v a lv e s is o r n a m e n te d w ith c o n cen tric, ir r e g u la r ly s p a c e d grow th lin e s . T h ese lin e s m a y be o b s o le te in the e a r ly s ta g e s , but w hen th ey are p r e s e n t, they u su a lly show rounded card in al e x t r e m it ie s ev en if the la te r ones a re angular. Short sp in es m a y be p r e s e n t on the a n terio r third of both v a l v e s . D is c u s s i o n . - - T his s p e c ie s of P u n c to s p ir ife r d iffers fr o m P. t r a n s v e r s u s in that P. t r a n s v e r s u s has n u m e r o u s, e v en ly sp a ced grow th lin e s and the m e s i a l fold is bilobed; fro m P. sp in o sa in that the la tter has ev en ly sp aced , rounded grow th lin e s , a s e m ic i r c u la r p e r ip h e r y , and is m u ch s m a lle r in s iz e than P. c a m p e s t r i s ; and fr o m P. k e n tu c k e y e n sis in that P. k en tu ck ey en sis p o s s e s s e s e v e n ly sp a c e d grow th lin e s and a s m a ll p lic a tio n in the bottom of the su lcu s. L o c a lity . - - 309. P U N C T O SP IR IF E R TR A N SVERSU S (M cC hesn ey, 1860) PI. 4, fig. 30 I860. S p irife r tr a n s v e r s a M cC h esn ey , D e sc . N ew P al. F o s s ., p. 42. 1915. S p irife rin a t r a n s v e r s a (M cC hesn ey), Bull. Sci. Lab. D en ison Univ., vol. XVII, p. 92, pi. XIII, fig s . 7, 8. One s p e c im e n of P u n c to s p ir ife r t r a n s v e r s u s w a s d is c o v e r e d in the E ly lim e s to n e . The su rfa ce orn am en tation and the s m a ll ridge in 67 the pedicle sinus s e e m to place this P u n ctosp irifer unm istakably in the sp e c ie s P. t r a n s v e r s u s . P. tr a n s v e r su s is usually a sso c ia te d with M ississip p ia n fauna. Mather, how ever (1915, p. 192), reported it from M orrow an rocks in A rk ansas. It is h ere rep orted from younger P e n n sylvanian rocks than heretofore. L o ca lity .- - 324. Phylum MOLLUSCA C lass PE L E C Y P O D A S everal s m a ll pelecyp od s are p resen t in the co llection s from the low er E ly lim e sto n e . T hese s p ecim en s are poorly p r e s e r v e d and som ew hat rare, being found at only one locality. T hree of th ese p e le c y pods are r e fe r r e d to the following genera: Genus A ST A R T E L L A Hall, 1858 A ST A R T E L L A sp. PI. 5, fig. 13 L o ca lity . - - 31 3. Genus NUCULANA Link, 1807 NUCULANA sp. PL 5, fig. 12 L o ca lity . - - 31 3. Genus CONOCARDIUM Bronn, 1834 CONOCARDIUM sp. PI. 5, figs. 14-15 L o ca lity . - - 31 3. C lass SCAPHOPODA Two scaphopods w ere co llected from the low er portion of the 68 section. They are r e fe r r e d to two co m m o n P en n sylvan ian genera. Genus D ENTALIUM Linnaeus, 17 58 DENTALIUM sp. ' PI. 5, fig. 28 L o c a lity . - - 31 3. Genus P L A G IO G L Y P T A P ilsb r y , 1898 PLA G IO G L Y PT A sp. Pl. 5, fig. 29 C la ss GASTROPODA Gastropods are m uch m o r e co m m o n ly r e p r e se n te d in the E ly lim e sto n e than pelecypods; h ow ever, they occur only ra re ly . B e ca u se a lm o st all the sh ells are sm a ll, it is a ssu m e d that they r e p r e se n t a sortin g phenom enon rather than an e c o lo g ic a l a sso c ia tio n . One genus, B a y le a , o ccu rs rather co m m o n ly in s ilic ifie d strata in the upper part of the Ely. H ow ever, the sh ells are quite sm all, averaging only about 5 m m in length. A few la rg e s p e c im e n s of a s p e c ie s of Euom phalus are p r e se n t in the collection; how ever, th ese are not silic ifie d and occur only as fra g m en ts. The m o s t co m m o n of the gen era p r e s e n t are lis te d below. Som e sp e c im e n s are r e fe r r e d only ten tatively to a genus. Genus M EEK OSPIRA U lrich and Scofield, 1897 M EEKOSPIRA sp. PI. 5, fig. 16 L o ca lity . --3 1 3. Genus ? LE PT O Z Y G A Knight, 1930 L E PT O Z Y G A sp. PI. 5, fig. 17 69 L ocality. - - 31 3. Genus BAYLEA Koninck, 1883 BAY LEA sp. PL 5, fig. 20 L o c a lity .--309. Genus PLATYCERAS Conrad, 1840 PLA TY CER A S sp. PL 5, fig. 19 L o cality. - - 31 3. Genus AMPHISCAPHA Knight, 1942 AMPHISCAPHA sp. PL 5, fig. 22 L o ca lity . - - 309. Genus EUOMPHALUS Sowerby, 1814 EUOMPHALUS sp. Not figured L o ca lity . - - 309- Genus BELLEROPHON Montfort, 1808 BELLEROPHON sp. PI. 5, fig. 23 L o cality. - - 31 3. C lass CEPHALOPODA A few orthoceracone w ere collected with s ilicified fo s s ils . One sp ecim en is here r efe rred to the genus P seu d o rth o cera s on the basis of a slight curvature of the adapical region. 70 Genus PSE U D O R T H O C E R A S Girty, 1911 PSE U D O R T H O C E R A S sp. PI. 5, fig. 18 L o c a lity . --3 1 3. P h ylu m A N N E L ID A C la s s C H A E T O PO D A Genus SPIRO RBIS L a m a r c k SPIRORBIS sp. PI. 5, fig. 21 — L o c a lit y . - - 309. P h ylu m A R T H R O PO D A C la ss T R IL O BITA O rder O PISTH O PA RID A Genus ? DITOM OP YGE N ew ell, 1931 PI. 5, fig s . 25, 26 F ou r p ygidia and a p o rtio n of a fr e e ch eek r e p r e s e n t the tr ilo - bites c o lle c te d fr o m the E ly lim e s to n e . A s p e c im e n of a v era g e s iz e has 15 axial s e g m e n ts and 11 p leu ra l s e g m e n ts . The p ygidial s e g m e n ts are sp in o se and the axial lobe s tr o n g ly elev a ted . The p leu ra l lo b es are bounded by a distinct, n arrow flan ge. T h e s e s p e c im e n s bear s o m e r e s e m b la n c e to P alad in as w e ll as to D ito m o p y g e . L o c a lity . --3 1 3. P h ylu m E C H IN O D E R M A TA Subphylum P E L M A T O Z O A C la ss CRINOIDEA The d o r sa l cup of a p r im itiv e inadunate crin oid w as c o lle c te d 71 from the lo w er part of the Ely. In this s p e c im e n there are three anal plates, and the radianal is actually in the basal c ir c le t. This E ly s p e c i m en r e s e m b le s P r ia s o c r in u s and P la x o c r in u s ; h ow ever, in those two genera, the anals are w e ll out of the b a sa l c ir c le t. This condition would se e m to indicate an e a r lie r evolutionary stage and probably r e p r e se n ts an u n d escrib ed genus. Inasm uch as the s p e c im e n is without a r m s and is the only one in the collection , it is not d escrib ed . L o c a lity . --3 1 5. C olum nals C rinoid colu m n als occur co m m o n ly in the low er part of the Ely and are p r e s e n t throughout the entire seq u en ce. EXPLA NA TIO N OF P L A T E 1 Fig. 1 - 3 - - Chaetetes favosus M oore and Jeffords. 1. T r a n s v e r se s e c tion, USC 5018, X45; 2. longitudinal section, USC 5019, X15; 3. tr a n s v e r s e section, USC 5018, X15. 4 - 6 - ~ Caninia torquia (Owen). 4. T r a n s v e r se sectio n of a large sp ecim en , USC 5020, XI 1/3; 5. longitudinal section. Tabu lae in this sp ecim en are broken, USC 5022, XI 1/2; 6. t r a n s v e r s e section of an im m atu re sp ecim en in which the thecae is eroded away, USC 5021, X2 1/2. 7- - Lophophyllidium sp. T r a n s v e r s e section, USC 5023, XI 1/2. 72 74 EX PL A N A T IO N OF P L A T E 2 Fig. 1 , 2 - - F u su lin ella devexa Thom pson. 1. Longitudinal section, USC 5024, X20; 2. t r a n s v e r s e section, USC 5025, X20. 3,4- - P ro fu su lin ella aff. P. reg ia T hom pson. 3. Longitudinal s e c tion, USC 5026, X20; 4. tr a n s v e r s e section , USC 5027, X20. 5- - M ille r e lla sp. T r a n s v e r s e section, USC 5028, X30. 6- - T extularia sp. A tr a n s v e r s e se c tio n som ew hat off cen ter, (sp e cim en lost), X25. 7 - - Syr ingopora sp. View of the su rfa ce of a colony, USC 5029, XI. 8 ,9~ ~ O rbiculoidea ca p u lifo r m is M cC h esn ey. 8. P e d ic le valve, USC 5030, XI; 9. external m old of a b rach ial valve, USC 5031, XI. 10- 1 6 - - R hipidom ella e ly e n s is, n. sp. 10-14. P e d ic le v a lv e ,b r a c h i al valve, an terior, p o s te r io r and side view of the holotype, USC 5032, XI; 15. p ed icle in terio r showing m u s c le s c a r s , USC 5034, XI; 16. b rach ial in terior, USC 5035, XI. 17- 1 9 ~ - Schizophoria resu p in oid es (Cox). B rach ial e x te r io r , pedicle e x te r io r and an terior view showing dental la m e lla e and m edian septa, USC 5037, X I. 2 0 - - R hipidom ella n ev a d en sis (Meek). P e d ic le in terior showing m u s c le s c a r s , USC 5038, X I. 2 1 -2 4 - - Welle re 11a sp. P e d ic le e x ter io r, an terior show ing p licate anterior c o m m is s u r e , b rach ial e x te r io r and side view, USC 5039, X3. 75 Fig. 2 5 - - Chonetina flem in g i (Norwood and Pratten). P ed icle exterior, USC 5041, XI. 26,27- - D erbyia aff. D. haesitan s (Dunbar and Condra). 26. P ed icle interior showing high m edian septum, USC 5042, XI; 27. p edicle exterior, USC 5043, XI. P L A T E 2 76 77 EXPLANATION OF PL A T E 3 All figu res XI Fig. 1 , 3 ,4 - - Linoproductus prattenianus (Norwood and Pratten). 1. P e d icle exterior, USC 5044; 3. brachial interior, showing m u sc le s c a r s , USC 5046; 4. cardinal p r o c e ss , USC 5047. 2 - - Linoproductus magnispirius Dunbar and Condra. P edicle exterior, USC 5045. 5 - 8 - - Antiquatonia h erm osan a (Girty). P ed icle exterior, side view, brachial exterior, view of the hinge-line, USC 5048. 9~ 11 - - Diaphragmus cf. D. fasciculatus (McChesney). 9. P ed icle exterior, USC 5049; 10. brachial interior showing dia phragm, USC 5051; 11. pedicle exterior of a sm a lle r s p e c i men, USC 5050. 12- 1 4 - - Antiquatonia e ly e n s is , n. sp. A nterior, side view, hinge- line of holotype, USC 5052. 1 5 -- D ictyoclostus am ericanus Dunbar and Condra. P ed icle e x terior of a very large sp ecim en , USC 5103. f 78 PLA TE 3 79 EX PLANATION OF P L A T E 4 Fig. 1 - 7 - - L is s o m a r g in ife r a nuda, n. sp. 1-5. P ed icle ex ter io r sh ow ing distribution of spines over the surface, brachial e x te r i or showing spin es along the h in ge-lin e, anterior, and side view of genoholotype, USC 5055, XI; 6. brachial interior, USC 5057, XI; pedicle e x te r io r showing faint costae, USC 5056, XI. 8-11 - - Antiquatonia e l y e n s i s , n. sp. B rach ial view of a partial valve, pedicle ex terio r, h in ge-lin e, side view, USC 5054, XI. 12- 1 4 - - Rhynchopora m a g n ico sta Mather. L ateral view, brachial exterior, p ed icle exterior, USC 5059, XI. 1 5 - - D ie la sm a bovidens (Morton). P ed icle ex terio r, USC 5060, XI. 16-21 - - Cranaena m in uta, n. sp. 16-19. P ed icle exterior, brachial ex terio r, side view, anterior view of holotype, USC 5061, X3; 20. interior view of h in g e-lin e showing p erforate hinge- plate, USC 5063, X3; 21. lateral view of a gerontic s p e c i m en showing crov/ded growth lin es, USC 5062, X3. I 2 2 - 2 9 ~ - P u n ctosp irifer c a m p e str is (White). 22-25, 28. B rach ial e x terio r, ped icle ex terio r, anterior, side view, h in ge-lin e, USC 5065, XI; 26. brachial interior, USC 5067, XI; pedicle interior of a distorted sp ecim en , USC 5066; XI; 29. pedicle ex terio r of a gerontic sp ecim en , USC 5068, XI. 3 0 - - P u n ctosp irifer tr a n sv e r s u s (M cChesney). A nterior of a sp e c im e n With the e a r s broken, USC 5069, XI. 80 Fig. 3 1 - 3 3 - - C om p osita a rg en tea (Shepard). A n te rio r, b ra ch ia l e x ter io r, p e d ic le e x te r io r , USC 5070, X I. 34, 3 5 - - C ru rith yris p lan ocon vexa (Shumard). L a tera l v iew , p ed icle ex te r io r , USC 5071, X3. 36, 37- - C leioth yrid in a o r b ic u la r is (M cC h esn ey). B rach ial ex te r io r , p ed icle e x te r io r of an ex fo lia ted sp e c im e n , USC 5072, X I. 38-41 - - H ustedia m i s e r i subsp. g ib b o s a , n. subsp. P e d ic le e x te r io r , brach ial e x te r io r , sid e vie w of the holotype, USC 5073, X I. 4 2 - 4 5 - - H ustedia rotunda, n. sp. H in g e -lin e , sid e view , b ra ch ia l e x te r io r , p e d ic le e x te r io r of the holotype, USC 507 5, X I. 81 P L A T E 4 10 12 17 18 ♦ . • w — 2 0 9 ■■< 5 ^ ' 23 ^ m r c, # ' # « p „# i * * ♦»“ •* # * * 22 28 30 3 1 39 40 — 41 42 4 3 44 45 82 E X P L A N A T IO N OF P L A T E 5 F ig. 1 ,2 - - H ustedia rotunda, n. sp. 1. Interior show ing sp ire, USC 5077, XI; 2. in terio r show ing ornam en tation of the jugum, USC 5104, X3. 3 - 7 ~ - S p irifer occiduus Sadlick. 3. P e d ic le in terior show ing thickening along the h in g e -lin e , USC 5078, XI; 4 ,5. b ra ch ia l e x te r io r , b ra ch ia l in terior, USC 5079, XI; 6,7. p e d ic le e x t e rior, p ed icle e x te r io r , USC 5080, X I. 8 - - C om p osita subtilita (Hall). P e d ic le ex te r io r , USC 5081, X I. 9~ 11 - - N e o sp ir ife r trip lica tu s (Hall). 9. P e d ic le e x te r io r show ing m u cro n a te e x t r e m it ie s , USC 5082, XI; 10. p ed icle e x te r io r of a p ortion of an e x t r e m e ly la r g e sp e c im e n , USC 5083, XI; 11. p ed icle e x te r io r of a ty p ica l s p e c im e n , USC 5102, X I. 1 2 - - Nuculana sp. Left valve of a p o o rly p r e s e r v e d s p e c im e n , USC 5085, X3. 1 3 - - A s ta r te lla sp. Right valve, USC 5084, X3. 14,1 5- - C onocardium sp. Left va lv e, card in al view of a v e r y s m a ll sp e c im e n , USC 5086, X3. 16 - - M e e k o s p ir a sp. Side view , USC 5087, X3. 1 7 - - L ep tozyga sp. Side view , USC 5089, X3. 1 8 - - P s e u d o r th o c e r a s sp. Side v ie w , USC 5091, X3. 1 9 __P la ty c e r a s sp. Side view , USC 5090, X3. 20- - B aylea sp. Side view , USC 5088, X3. 2 1 - - S pirorbis sp. Tightly co iled sh ell, USC 5092, X3. 22- - A m p h isca p h a sp. B a sa l view , USC 5096, X3. 83 Fig. 2 3 - - B eller ophon sp. Back view showing ornam entation, USC 5093, X3. 2 4 --C r in o id cup in w hich the anal plate is shown within the basal circlet, USC 5097, XI. 2 5 , 2 6 - - ? D itom op yge. 25. Pygidium , USC 5098, XI; 26. a fr e e cheek and a portion of a pygidium, USC 5099, XI. 27--C on u lariid . E xternal m old, USC 5100, X I.; 2 8 - - Dentalium sp. Side view showing ornamentation, USC 5094, 29~~P lagioglypta sp. Side view . Spirorbis is en cru sted on the surface, USC 5095, XI. 30- - A rch im ed es sp. Side view of the sp ire, USC 5101, X I. REGISTER OF LOCALITIES 3 09- - SW 1/4, NE 1/4, NW 1/4, s e c . 6, T16N, R59E, Illipah quadrangle. T ributary to Cottonwood C reek. Zone of s ilic ifie d f o s s i l s lie s about 100 ft. str a tig r a p h ic a lly above C haetetes - P r o fu s u lin e lla zone at fork in dry trib u tary to Cottonwood C reek. 3 1 0 - - N W 1 /4 , se c . 6, T16N, R 59E. C h a e te te s -P r o fu s u lin e lla zone s tr ik e s north p erp en d icu la r to the canyon and cro p s out just below the fork of the c r e e k b elo w lo c a lity 309. 311 — C enter of s e c . 6, T17N, R59E, Illipah quadrangle. A s ilty bed cro p s out at the su m m it of the ridge about 312. 3 1 2 - - C e n t e r , E 1/2, s e c . 12, T17N, R58E, Illipah quadrangle. A m a s s i v e lim e sto n e w ith nodular ch ert and few f o s s i l s cro p s out above a broad c o v e r e d slop e. The outcrop m a y be r ea c h e d by clim b in g the h ill e a s t of the in te r s e c tio n of H am ilton road and U. S. Highway 50. The broad slop e li e s just above the top of the E ly L im e sto n e . 3 1 3 -- C enter, S 1/2, s e c . 10, T16N, R58E, Illipah quadrangle. F o s s i l s occur abundantly on the talus slop e on the sou th east w a ll of H arris Canyon. 3 1 4 - - C e n t e r , S 1/2, s e c . 10, T16N, R59E, Illipah quadrangle. F o s s i l s o ccu r at the rim of the w e s t side of H a r r is Canyon, about fifty p a c e s north of lo c a lity 313. 31 5 - - Sum m it of M okom oke ridge n o rth w est of H am ilton and north of the H a rris Canyon road. Sec. 8, T16N, R58E, Illipah quadrangle. 85 3 1 6 -- White P in e County, N evada. L im e sto n e w ith w ood grain texture ex p o sed in a road cut on the e a s t sid e of H am ilton road 900 feet above p ro m in en t ridge of D iam on d P e a k Q uartzite. E 1/2, s e c . 32, T17N, R58E, Illipah quadrangle. 3 1 7 - - S E 1 / 4 , s e c . 27 (projected), T17N, R61E, R eipetow n quadrangle. F r o m a bluff of lim e s to n e along the c r e s t of the E gan Range, 200 yard s north of the rounded peak. 3 1 8 - - On a spur south of Dutch John M ountain near the top of the hill and at the foot of the m o s t p ro m in en t bluff. The spur can be r e a c h e d by going 2.0 m ile s w e s t on S tew art's Ranch road from the junction of U. S. Highway 9 3 and the A tlantic Mining D is tr ic t road, then bearin g w e s t at the curve of the road to K ix m iller Sum m it for 0.8 m il e s . N orth w est c o r n e r s e c . 34, T6N, R56E, L in coln County, N evada. 319- - L im e sto n e s and s h a le s r e a c h e d by going 0.2 m ile north of Skunk Spring, then w e s t up the c r e e k bed 0.3 m ile to a dry fa lls . F o s s i l s occur in the to p m o st bed of the fa lls. P hoto 38U -34, C onfusion Range, M illard County, Utah. 3 2 0 - - N e a r P r e s to n , White P in e County, Nevada, in NE 1/4, s e c . 14, T14N, R61E, as shown on E ly G razing D istr ic t m ap. About one m ile south of the in te r s e c tio n of the E ly - P r e s t o n road and U. S. Highway 6. 3 2 1 - - S e c . 10, T13N, R61E, north of P r e sto n , White P ine County, Nevada. 3 2 2 - - NW 1/4, s e c . 17, T6N, R63E, L in coln Co., N evada. F lat ly in g beds w e s t of e a s t sid e of range b etw een Trough Canyon and H o r se 87 Spring, so u th ea st of Sunny sid e, N evada. 3 2 3 - - N orth end of F o x M ountains in lim e s to n e beneath v o lc a n ic s north of road. Photo 2 -9 0 , E 1/2, s e c . 13, T4N, R61E, south of Sunny- sid e, N ye County, Nevada. 3 2 4 - - Grant Range in s e c . 30, T6N, R59E, Nye County, N evada. 3 2 5 - - Southern Egan Range, near NE c o r n e r s e c . 26, T6N, R 62E ( F a ir child photo 1-17), L in coln County, Nevada. 3 2 6 - - N orth of T im b er P a s s Road, n ear lo c a lity 327, on the w e s t side of the sou thern E gan ran ge, su rrou n ded by v o lc a n ic s . Photo 2 -1 1 1 . 3 2 7 - - T im b er P a s s Mt., E a s t of White R iver V alley n ear the junction of - White P ine, Lincoln, and Nye C ounties, Nevada, in T10N, R62E. 3 2 8 - - Southern E gan Range, L incoln County, Nevada. T8N, R62E, north of Sunnyside, N evada. 3 6 1 - - Low bluff of lim e s to n e c r o s s in g north or m a in fork of c r e e k a few hundred feet e a s t of lo c a lity 309 and about 2 50 fe e t above the top of the E ly L im e sto n e . C enter, N 1/2, N 1/2, s e c . 6, T16N, R59E, Hlipah quadrangle, White P ine County, Nevada. M EA SU R ED SECTIONS Section A. T16N, R59E, s e c . 6. M e a su r e d ea stw a rd up interm ittent tributary to Illipah C reek at the n orthern edge of the section . Top of Section F e e t P e r m ia n S ystem "Rib Hill" Sandstone 1. C on glom erate, angular ch ert p eb b les in lim e sto n e m a trix . T hree bands of the c o n g lo m er a te are s e p a rated by w eak a r g illa c e o u s lim e s to n e . C on glom erate * bands are 1 foot thick; s e c tio n not m e a s u r e d ____ P en n sy lv a n ia n S y stem ........................................................ H oliday L im e sto n e 2. M ostly co v ered , silty buff lim e sto n e w h ere ex p o sed 124 3. P a r tia lly covered , blotchy, hard lim e s to n e w here exp osed . B ryozoan s in the upper 20 feet 62 4. L im e sto n e, m a s s iv e , light gray, m ed iu m grain, hard. B ryozoan at top. 80 5. C overed. 116 6. L im e sto n e, m a s s iv e , light gray, hard, fo r m s r e sistant ledge, f o s s il d e b r is. 87 88 89 F eet 7. L argely covered, yellow ish silty lim eston e w here exposed. 128 8. L im estone, light gray to buff, becom ing blotchy to w ard the top, sam e nodular chert. 88 9. L argely covered, silty buff lim eston e w here exposed. 68 10. L im eston e with nodular chert at the bottom, b e c o m ing m a s s iv e toward the top. 47 11. L im estone, silty, buff, thin-bedded. 36 12. A s e r ie s of sandy lim eston e m em b ers interbedded with light gray m a s s iv e lim e sto n e s a foot or so thick 183 13. L im estone, m a s siv e , light gray, very fo ssilife ro u s, f o s s il debris, Caninia. 27 14. L im eston e, light gray, m a s s iv e , a few chert nodules. Chaetetes and Caninia. 23 15. L im eston e, light gray, m a s s iv e with nodular chert. 50 16. L im eston e, m a s s iv e , light gray. Caninia abundant in the upper 4 feet. 20 17. L im estone, hard, light gray with banded chert. 73 18. L im estone, yellow ish silty, thin»bedded 114 Ely L im estone 19. P artially covered. Y ellow ish to buff lim eston e with thick bands of chert w here exposed. 110 20. L im estone, dark gray, nodular chert at base, b e com ing lighter gray and sandy toward top. Very fossiliferou s; silicified brachipods occur at top of zone; locality, 309. 21. L im estone, m a s siv e with no chert. Chaetetes and Pr ofusulinella distributed throughout zone. 22. S eries of cherty lim esto n es interbedded with m edium gray lim e sto n e s. 23. L im estone, cherty bands 1 to 2 inches thick, form s slight ridge. 2^1. L im estone, dark gray with thick bands of chert 2 to 4 inches. F o s s ils v ery sp arse. 25. P artially covered, silty, buff lim eston e w here exposed. 26. P artially covered, cherty beds in w eak lim eston e w here exposed. 27. - P artially covered, w eak silty lim eston e w here e x posed, form s gentle slope. 28. P artially covered, weak silty lim eston e, interbedded with som e m a s s iv e lim esto n e w here exposed. 29. Cherty lim eston e, 20 per cent chert; fo rm s sm all ridge. 30. A s e r ie s of alternating, cherty, weak beds; covered slopes with a few light gray lim e sto n e s. 31. Covered. 32. L im estone, light gray, m a s siv e , with nodular chert becoming som ew hat sandy toward the top. 33. Cherty lim eston e, thin bands of chert, chert 40 per cent. 90 F eet 60 39 167 15 66 84 40 60 71 7 139 67 17 10 34. C overed. 35. Cherty lim esto n e, chert bands 1/2 inch to 3 inches thick, 45 per cent chert. 36. L im eston e, m a s s iv e , chert str in g e r s in light gray m atrix. 37. Cherty lim e sto n e , thin bands of chert, 1/2 inch to 3 inches thick, 45 p er cent chert. 38. Cherty lim esto n e, nodular, som ew hat silty. 39. Cherty lim esto n e, banded chert in low er half b e c o m ing nodular toward the top. Surface staining 25-30 p er cent. 40. L im eston e, m a s s iv e , light gray with som e nodular chert, highly fractured, fra ctu res not filled, few f o s s ils . Fault Contact Mis sissip p ia n or P ennsylvanian S y ste m s Chainman Shale or Diamond P eak Quartzite Section not m ea su red . 91 F eet 31 44 32 40 69 64 ___7J_ 2629 Section B . T17N, R58E, se c . 12. M easu red eastw ard up the spur 100 yards south of the in tersection of H am ilton Road and U. S. 50 w e s t of' M oorm an Ranch, Nevada. 92 Top of Section F e e t P e r m ia n S ystem "Rib Hill" Sandstone t 1. C onglom erate, subrounded chert p eb b les in lim e sto n e m atrix; 1-foot beds sep a ra ted by s ilic e o u s , buff l i m e stone; sectio n not m e a s u r e d . ____ P en n sylvan ian S y stem H oliday L im esto n e 2. L im e sto n e, thin-bedded, cherty, buff. 33 3. L im e sto n e, buff, thin-b ed ded s ilic e o u s , b ry o zo a n s. 2 4. L im e sto n e, thin-bedded, cherty, buff. 57 5. Criquina, light gray, f o s s i l d eb ris. 2 6. C overed. 87 7. L im e sto n e, m a s s iv e , light gray nodular chert; Caninia at top of bed. 40 8. L im e sto n e, thin-bedded, som ew h at sandy, cherty. 37 9. L im e sto n e, m a s s iv e , c o a r s e c r y sta llin e , so m e f o s s il d eb ris. 35 10. C overed. 140 11. L im e sto n e, dark gray, su rface pitted on w eath erin g. 21 12. C overed. 30 13. L im e sto n e, silty, buff, b ryozoan s. 6 14. C overed. 37 93 F e e t 15. L im e sto n e , light gray, m a s s i v e w ith la y e r s of nodular ch ert. 36 16. L im e s to n e , light g ra y w ith nodular chert; fo r m s p ro m in en t rid ge. 80 17. L im e s to n e , light gray, m a s s i v e w ith s o m e banded ch ert, lo c a lity 311. 240 18. L im e s to n e , gray, m a s s i v e , nodular chert; C aninia o c c u r s s p a r se ly ; C h a e tetes o c c u r s in p a tch es, lo c a lity 312. 54 19. C o vered . 80 20. L im e sto n e , y e llo w is h , silty , th in -b ed d ed . 11 21. C o vered . 230 E ly L im e s to n e 22. L im e sto n e , m a s s i v e at b a s e , b e c o m in g sandy to w a rd the top. 57 2 3. L im e s to n e , th in -b ed ded , sandy, g ray to buff. 69 24. L im e sto n e , m a s s i v e , light gray; nodular c h e r t at base; p itted w e a th e r in g s u r fa c e . 85 25. L im e s to n e , light gray, s ilic if ie d f o s s i l s . 9 26. A ltern atin g banded c h e r t and lim e s to n e ; c h ert bands up to 4 in ch es thick. 47 27. A ltern a tin g banded c h e r t and lim e s to n e ; C h a etetes and P r o fu su lin e lla o ccu r in p a tc h e s in the upper 4 feet; P r o fu s u lin e lla w e ll p r e s e r v e d in c h ert n odules throughout bed. 34 94 F e e t 28. L im e sto n e, light gray with ch ert bands 4 to 8 inches thick. 53 29. A lternating dark g ray lim e s to n e s , sandy beds and ch ert bands; f o s s ilife r o u s . 53 30. C overed. 94 31. L im e sto n e, light gray, m a s s i v e , w ith nodular chert. 28 32. L im e sto n e, light gray; a few Caninia 6 33. L im e sto n e, light gray, m a s s i v e w ith nodular chert. 39 34. L im e sto n e, m ed iu m gray, banded chert; bands 1/2 inch thick. 15 35. L im e sto n e, light gray; m a s s i v e nodular chert. 19 36. L im e sto n e, platy; fo r m s a w eak slo p e. 14 37. L im e sto n e, light gray, rather resistan t; fo r m s a slight ridge. 14 38. L im e sto n e, light gray, m a s s i v e , w ith chert bands 4 inches thick; so m e nodular chert. 14 39. L im e sto n e w ith nodular chert. 20 40. Cherty lim e s to n e , alternating bands of chert and l i m e stone, 4 to 10 in ches thick; chert c o m p r is e s about 50 per cent of ex p o su re. 8 41. L im e sto n e, light gray, m a s s i v e , w ith nodular chert. 52 42. L im e sto n e, brow nish to buff w ith chert strin g ers; sligh tly f o s s i l i f e r o u s . 14 43. L im e sto n e, light gray with thin ch ert bands; a few brachiopods on the w ea th ered su rfa ce. 1 2 9 • 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 95 F eet L im eston e, m a s s iv e , light gray, slightly fo s silife r o u s. 19 L im estone, gray to buff, deeply w eathered; a few f o s s ils . 63 L im eston e, buff, thin band of b ryozoans. 2 A lternating s e r ie s of lim e s to n e s and cherty beds; le s s chert toward the b ase. 100 Cherty lim esto n e, 70 p er cent chert; chert bands 1/8 to 1 inch; prom inent ridge fo r m e r . 19 P artially covered, w eak lim e sto n e with so m e chert; fo rm s a gentle slope. 63 Cherty lim esto n e, chert; ch ert bands 1 inch thick. 22 L im eston e, light gray; both banded and nodular chert separated by 8 - inch bands of lim e s to n e . 35 L im eston e, light gray, m a s s iv e , with nodular chert. 19 Cherty lim eston e; bands of chert 1 inch thick; 25 to 30 per cent chert. 28 L im eston e, som e banded chert; fo rm s a w eak slope. 14 Cherty lim estone; thin bands of chert 1 inch thick, 50-60 per cent chert; fo rm s prom inent ridge. 12 L im eston e, light gray, weak; f o s s il deb ris. 11 Cherty lim esto n e, 60 p er cent chert; chert bands 1 to 3 inches thick. 31 L im eston e with banded chert; 20-2 5 per cent chert. 67 Cherty lim estone; chert bands 1/2 inch to 4 inches thick; 70 per cent chert, gives whole bed ru st-b row n 96 F eet appearance. 12 60. Cherty lim eston e; v e r y f o s s i lif e r o u s . 2 61. Cherty lim eston e; chert bands 1/2 inch to 4 inches thick; 70 per cent chert, gives w hole bed ru st-brow n appearance. 23 62. C overed talus slope. 51 63. L im eston e, light gray, m a s siv e ; v e r y fo ssilife r o u s. 6 64. L im eston e, platy, argillaceous; with chert strin g ers toward the top; fo s s ilife r o u s . 44 2774 Fault Contact M iss is sip p ia n or P enn sylvanian S y s te m s Chainman Shale or Diam ond P eak Quartzite Section not m ea su red . Section C . T18N, R58E, se c . 24. M ea su red sectio n eastw ard along the tributary due e a st of Divide Spring. The top of the section is situated 65 feet stratigrap h ically below the base of a Thysanophyllum -b earin g bed near the base of the "Rib Hill" sandstone. Top of Section F eet P e r m ia n System "Rib Hill" Sandstone 1. C onglom erate, sub-rounded chert pebbles occur in * 97 F eet w hite li m e y m atrix; s e c tio n not m e a s u r e d . ____ P en n sy lv a n ia n S y ste m Holiday L im e sto n e 2. L a r g e ly c o v e r e d , y e llo w is h to v a rieg a ted , s ilty l i m e stone, w ith s o m e ch e r ty m e m b e r s w h e re e x p o sed . 310 3. L im e sto n e , dark gray w ith c h ert s t r in g e r s . 13 4. L im e sto n e , thin -b ed ded silty, y e llo w is h to buff. 51 5. L im e sto n e , m a s s i v e , light gray, w ith nodular chert; s u rfa ce is pitted on w ea th erin g . 26 6. M ostly covered ; buff, s ilty to sandy lim e s to n e w h e r e e x p o sed . 126 7. L im e sto n e , light gray, m a s s i v e w ith s o m e chert; s ilic ifie d brach iop od s o ccu r in lo w e r 2 feet. 9 8. S e r ie s of bedded, platy lim e s to n e s , inter bedded w ith silty m e m b e r s . 56 9. L im e sto n e , m a s s i v e , light g ray w ith o c c a s io n a l chert; r e sista n t, fo r m s le d g e . Z0 10. Silty, buff c o lo r e d lim e s to n e w ith colonial c o r a ls . 6 11. L im e sto n e , m a s s i v e , light g ray w ith o c c a s io n a l chert; r e s is ta n t, fo r m s le d g e . 24 C o v ered Contact 641 E ly L im e sto n e Section not m e a s u r e d . 98 Section D. T16N, R58E, s e c . 32. M e a su r e d ea stw a rd from 0.1 m ile e a st of H am ilton Road to the top of Hill 8688. Section begins at the top of Hill 8688 beyond w hich are gen tly rolling slo p e s. Top of S ection F e e t P e r m ia n S y stem "Rib Hill" Sandstone Covered; se c tio n not m e a s u r e d . P en n sy lv a n ia n S ystem E ly L im e sto n e 1. L im e sto n e, light gray, hard; w ith thick chert bands; fo r m s p rom in en t ridge. 13 2. C overed. 37 3. L im e sto n e , w ith thick bands of chert, 4 to 6 inches thick. 7 4. L im e sto n e, gray to y e llo w is h gray, m ed iu m grained; chert s tr in g e r s , a few f o s s i ls , lo c a lity 316. 43 5. Talus slope. 51 6. L im e sto n e , v e r y light gray with pitted w eath erin g surface; fo r m s p rom in en t ridge. 6 7. L im e sto n e, light gray, m a s siv e ; w ith chert s tr in g e r s . 40 8. L a rg ely covered; e x p o s u r e s of m a s s i v e lim e s to n e with crin oid al d eb ris w h e re ex p o sed . 171 9. L im e sto n e, m a s s iv e , light gray, so m e nodular chert; fo r m s prom in en t ridge. 36 99 ;et 10 5 56 10 29 18 47 47 2 12 55 55 24 86 L im estone, som e banded chert. Cherty lim esto n e, 30 per cent chert; thin bands of chert; prom inent ridge fo rm er. Talus slope; occasion al exposure of light gray l i m e stone. L im eston e, light gray, resistant; nodular chert; fo rm s s m a ll ridge. Talus slope. L im eston e, light gray, m a s siv e ; fo rm s s m a ll cliff. L argely covered; light gray lim e sto n e with thick chert stringers; f o s s i lif e r o u s . Cherty lim eston e; chert bands 1/2 inch thick stand out as stained ridges; lim esto n e fo rm s prom in en t ridge. L im eston e with chert stringers; fo s s ilife r o u s . Cherty lim eston e; chert bands 1/2 inch thick stand out as stained rid ges. L im eston e, blotchy; som e chert Covered; w eak slope. L im eston e, hard, light gray to brown; fo ssilife r o u s; fo rm s prom inent ridge. L im eston e, gray to briwnish, som ew hat sandy, l o cally cro ss-b ed d ed ; p iso litic structure. 100 Fault Contact F e e t M i s s is s ip p ia n or P en n sy lv a n ia n S y s te m s Chainm an Shale or D iam ond P e a k Q uartzite S ectio n not m e a s u r e d . Section E . T16N, R62E, s e c . 18. M e a su r e d southward, beginning 0.5 m ile due south of the ch urch in Lane, N evada, and continuing to the peak on the sou th ern boundary of se c tio n 18, 0.3 m ile so u th w est of S a x ton P p .i'-. Top of S ectio n F e e t P en n sy lv a n ia n S y ste m E ly L im e sto n e 1. L im e sto n e , light gray, hard, nodular chert; C haetetes o c c u r s patchily. 12 2. Weak slope; blotchy, light gray, lim e s to n e in ta lu s. 17 3. L im e sto n e , light gray, m a s s i v e , hard; fo r m s p rom in en t ridge. 20 4. L im e sto n e , light gray, blotchy, weak; fo r m s gentle slop e. 33 5. L im e sto n e , silty, brow nish, w eak . 2 6. L im e sto n e, m ed iu m grained, light gray, hard, blotchy; ridge fo r m e r . 12 7. C overed . 92 8. L im e sto n e , dark gray, blotchy, w eak. 34 9. 1 0 . 1 1 . 1 2 . 13. 14. 15. 16. 17. 18. 19. 2 0 . 2 1 . 2 2 . 23. 24. 25. 26. 27. 28. 101 F e e t C overed . 16 L im e sto n e , light gray, m a s s iv e ; fo r m s gentle slo p e. - 16 C overed . 13 L im e sto n e , light gray, m a s s iv e ; fo r m s s m a ll ridge. 12 W eak slo p e, dark g ray lim e sto n e ; f o s s i l s in talu s. 21 L im e sto n e , sandy, b ro w n ish to buff, c r o ss-b e d d e d ; fo s s ilife r o u s ; fo r m s s m a ll led g e. 11 C overed . 32 L im e sto n e , m a s s i v e , m ed iu m gray, hard; fo r m s p ro m in en t ridge. 30 C overed . 132 L im e sto n e , m ed iu m grain, dark gray; fo s s ilife r o u s; fo r m s p ro m in en t rid ge. 38 W eak slope; dark g ray lim e s to n e w ith f o s s i l s in t!alus. 28 L im e sto n e , light gray, m a s s iv e ; fo r m s s m a ll ridge. 6 C overed. 28 L im e sto n e , m a s s i v e , light gray; fo r m s p rom in en t ridge. 20 W eak slope; light g ray lim e s to n e talus. 71 L im e sto n e , dark gray, m a s s i v e , hard; fo r m s p r o m i nent rid ge. 15 L im e sto n e , light gray; no chert; lightly fractu red . 36 C overed . 109 L im e sto n e , m a s s i v e , dark gray, lightly fractured; f o s s i l d eb ris; fo r m s p ro m in en t ridge. 33 C overed . 45 102 F eet 29. L im e sto n e, m a s s iv e , dark gray; fractu red . 30 30. P a r tia lly covered; lim e sto n e , dark gray; fo s silife r o u s . 59 31. C overed. 122 32. L im e sto n e, light gray, m a s s iv e ; f o s s i l debris; slightly fractu red . 60 33. L im e sto n e, light gray to buff, hard; fo r m s light ridge. 50 34. L im e sto n e, light gray, m a s s iv e ; f o s s ilife r o u s . 52 35. L im e sto n e, light gray, m ed iu m cr y sta llin e , m a s s i v e . 53 36. L a r g e ly c o v e r e d lim esto n e; light gray. 56 37. L im e sto n e, c?ark gray, sligh tly fra ctu red and filled w ith calcite; not w e l l exp osed . 20 38. L im e sto n e, dark to m ed iu m gray; sligh tly fractu red and filled w ith calcite; not w e ll exp osed . 22 39. L im e sto n e, dark gray, hard; sligh tly f o s s ilife r o u s . 44 40. P a r tia lly covered; dark gray lim esto n e; fractu red and filled with ca lc ite . 53 41. L a rg ely covered; hard, dark gray lim e sto n e in talus. 44 42. C overed. 157 D ep ositional Contact M is s is s ip p ia n S ystem Chainman Shale L a rg ely covered , black to gray, platy to fiss ile ; s e c tio n not m e a s u r e d . 1756 R E F E R E N C E S R E F E R E N C E S Condra, G. E., and E lia s, M. K., 1944, Study and r e v isio n of A r c h i m e d e s (Hall): Geol. Soc. A m er. Spec. P a p er 53. Dott, R. H., Jr., 1955, P en n sy lv a n ia n stratigraphy of Elko and N orthern Diam ond ran ges, n o rth ea stern Nevada: Bull. A m er. A s s o c . P e tr o l. Geol., vol. 39, no. 11, pp. 2 2 11-2305. Dunbar, C. O., and Condra, G. E., 1932, Brachiopoda of the P e n n s y l vanian s y s te m in Nebraska: N eb rask a Geol. Survey Bull. 5, S er. 2. Easton, W. H., 1944, R ev isio n of Campophy 11 um in North A m eric a : Jour. P aleon t., vol. 18, no. 2, pp. 119-132. __________ , 1951, M iss is s ip p ia n cuneate co ra ls: Jour. P aleon t., vol. 25, no. 3, pp. 380-404. __________ , et a l., 1953, R ev isio n of stratigrap h ic units in the G reat B a sin:__Bull. A m e r . A s s o c . P e tr o l. Geol., vol. 37, no. 1, pp. 143-151. E ch o ls, D. J., 1948, N ew s Report: M icropaleontology, vol. 4, no. 2, p. 225. E lia s, M. K., 1957, Late M is s is s ip p ia n faunas from the Redoak Hollow form ation of southern Oklahoma, P a r t II, Brachiopoda: Jour. P aleon t., vol. 31, no. 3, pp. 387-527. Girty, G. H., 1903, The C arboniferous form ation s and faunas of C o lo rado: U. S. Geol. Survey P rof. P a p er 16. , , 1920, C arboniferous and T r ia s s ic faunas: U. S. P rof. P a p er 111, p p . 641 - 6 5 7 . __________ , 1927, D escrip tio n s of new s p e c ie s of C arboniferous and T r i a s s i c f o s s ils : U. S. Geol. Survey P rof. P ap er 152, pp. 4 1 1 -4 4 6 . __________ , 1935, An u n reco rd ed stru ctu re in cer ta in se m ir e tic u la te p ro - ducti: Jour. P aleon t., vol. 9. no. 1, pp. 7 -9 . H ose, R. K., and Repenning, C. A., 1959, Stratigraphy of P enn sylvanian, P e r m ia n and lo w er T r ia s s ic rocks of the Confusion range, w e s t - cen tral Utah: Bull. A m er. A s s o c . P e tr o l. Geol., vol. 43, no. 9, pp. 2167-2196. I 104 105 Huang, T. K., 1933, Late P e r m ia n Brachiopoda of southw est China: P aleontologia Sinica, Ser. B, vol. 9, fa sc. 1. Jeffords, R. M., 1942, Lophophyllid co ra ls from low er P ennsylvanian rock s of K ansas and Oklahoma: K ansas Geol. Survey Bull. 41, pp. 185-260. Lane, B. O., I960, The E ly lim e sto n e in the vicin ity of M oorm an Ranch, Nevada: Intermountain A s s o c . P etr o leu m G eologists, Guidebook to the geology of E ast Central Nevada, pp. 114-116. Langenheim , R. L., et a l., I960, P r e lim in a r y report of the geology of the E ly No. 3 quadrangle, White Pine County, Nevada: Inter m ou n tain A s s o c . P etr o leu m G eologists, Guidebook to the geology of E ast Central Nevada, pp. 148-156. Lawson, A. C., 1904, The copper deposits of the Robinson Mining D is trict, Nevada: Univ. C alifornia Pub. Geol., vol. 4. M ather, K. F., 1915, The fauna of the M orrow group of A rkansas and Oklahoma: Bull. Sci. Lab. D enison Univ., vol. 18, new s e r . 58, pp. 59-284. Meek, F. B., 1877, Paleontology: U. S. Geol. Expl. 40th P arallel: vol. 4, pt. 1. M iloradovich, B. V., 1945, Som e data on the m orphology of productid sh ells: Acad. Sci., U.S.S.R., Ser. Biol., no. 4, pp. 485-500. M orningstar, Helen, 1922, P o ttsv ille fauna of Ohio: Geol. Survey Ohio Bull. 25, 4th ser. M oore, R. C., F rye, J. C., and Jewett, J. M., 1944, Tabular d e s c r ip tions of outcropping rocks in Kansas: Kansas Geol. Survey Bull. 52, pt. 4, pp. 141-212. __________ , and Jeffords, R. M., 1945, D escrip tion s of low er P e n n s y l vanian co ra ls from T exas and adjacent states: T exas Univ. Bull. 4401, pp. 63-208. __________ , 1949, D ivisions of the P ennsylvanian sy ste m in Kansas: Kansas State Geol. Survey Bull. 83, Univ. Kansas Pub., Murphy, D. R., 1954, Fauna of the M orrow an rocks of central Utah: Brigham Young Univ. R es. Studies, Geol. Ser., vol. 1, no. 3. North, F. J., 1920, On Syringothyris W inchell and certain Carboniferous Brachiopoda r e fe r r e d to Spiriferina D'Orbigny: Quart. Jour. Geol. Soc. London, vol. 76, pp. 162-227. P lu m m er , F. B., 1920, The Carboniferous rocks of the Llano region of central Texas: T exas Univ. Pub. 4329. 106 Sadlick, W alter, 1960a, Some p relim in a ry a sp ects of Chainman S tra tigraphy: Intermountain A s s o c . P etr o leu m G eologists, Guidebook to the geology of E ast Central Nevada, pp. 81-90. __________ , 1960b, New nam e for Spirifer o ccid en talis (Girty) and its g e ologic history: Jour. Paleontology, vol. 34, no. 6, pp. 1210-1214. Schuchert, C harles, and Cooper, G. A., 1932, Brachiopod gen era of the suborders Orthoidea and P entam eroidea: M em . Peabody M us. Nat. H ist., vol. 4, pt. 1. Spencer, A. C., 1917, G eology and ore deposits of Ely, Nevada: U. S. Geol. Survey Prof. P ap er 96. Steele, Grant, I960, P en n sy lv a n ia n -P e r m ia n stratigraphy of e a s t - c e n tral Nevada and adjacent Utah: Intermountain A ss o c . P etro leu m G eologists, Guidebook to the geology of E ast Central Nevada, pp. 91-113. Stehli, F. G., 1954, Low er L eonardian Brachiopoda of the S ie r r a Diablo: Bull. A m er. Mus. Nat. H ist., vol. 105, art. 3. Thompson, M. L ., 1942, P enn sylvanian in New M exico: N ew M exico School M ines Bull. 17. W eller, Stuart, 1898, A bibliographic index of North A m e r ic a n C arbon iferous in vertebrates: Bull. U. S. Geol. Survey, no. 153. White, C. A., 1877, Report upon the invertebrate fo s s ils , etc.: U. S. Geog. Survey W. 100th M erid., vol. 4, pt. 1. UNITED 8TATE8 l RTMENT OF THE INTE GEOLOOICAL 8URVEY ILLIPAH QUADRANGLE NEVADA-WHITE PINE CO. 15 MINUTE SERIES <TOPOORAPHIC) flo O O O O P E E T I R , 80 E . STATE OF NEVADA CHARLES H. RUSSELL, GOVERNOR VERNON E. SCHEID, DIRECTOR, BUREAU OF MINES U 7*0000 [Feet LEGEND Holiday f o r m a lly limes font M a a s u r td •action * > ' Pennsylvanian H [ roitn "

Linked assets

University of Southern California Dissertations and Theses

Conceptually similar

PDF

Paleoecology And Stratigraphy Of Pre-Kaibab Permian Rocks In The Ely Basin, Nevada And Utah

PDF

The Origin And Distribution Of Glauconite From The Sea Floor Off California And Baja California

PDF

Sedimentary History Of The Early Pliocene In The Los Angeles Basin, California

PDF

Facies Variation And The Miocene-Pliocene Boundary In Southern California

PDF

The Stratigraphy, Foraminifera, And Paleoecology Of The Montesano Formation, Grays Harbor County, Washington

PDF

Ultrastructure Of Tests Of Some Recent Benthic Hyaline Foraminifera

PDF

Neogene to recent Naticidae (Mollusca : Gastropoda) of the eastern Pacific

PDF

Continental Slopes Of The World

PDF

Heavy Minerals In Sediments Of Southern California

PDF

Continental Margin From San Francisco, California, To Cedros Island, Bajacalifornia

PDF

Sediments Of The Southern California Mainland Shelf

PDF

Oceanography And Late-Quaternary Planktonic Foraminifera, Southwestern Indian Ocean

PDF

Ecology And Paleoecology Of Hudson Bay Foraminifera

PDF

Late-Neogene Paleomagnetic And Planktonic Zonation, Southeast Indian Ocean - Tasman Basin

PDF

Distribution Of Foraminifera And Radiolaria In Sediments Of The Scotia Sea Area, Antarctic Ocean

PDF

Zoogeography And Ecology Of Polychaetous Annelids Of The Super-Family Eunicea Off Western Mexico

PDF

The Cumacea (Crustacea, Peracarida) Of California: Systematics, Ecology And Distribution

PDF

Geology In The Junior College

PDF

Recent And Upper Pleistocene Sediments Of The Southwestern Portion Of Losangeles County, California

PDF

The Geology Of Parts Of The Redrock Mountain, Warm Spring, Violin Canyon,And Red Mountain Quadrangles, Los Angeles County, California

Asset Metadata

Creator Lane, Bernard Owen (author)

Core Title The Paleontology And Stratigraphy Of The Ely Group In The Illipah Area Ofnevada

Degree Doctor of Philosophy

Degree Program Geology

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag Geology,OAI-PMH Harvest

Language English

Contributor Digitized by ProQuest (provenance)

Advisor Easton, William H. (committee chair), Bandy, Orville L. (committee member), Stone, Richard O. (committee member)

Permanent Link (DOI) https://doi.org/10.25549/usctheses-c18-257437

Unique identifier UC11358709

Identifier 6203737.pdf (filename),usctheses-c18-257437 (legacy record id)

Legacy Identifier 6203737.pdf

Dmrecord 257437

Document Type Dissertation

Rights Lane, Bernard Owen

Type texts

Source University of Southern California (contributing entity), University of Southern California Dissertations and Theses (collection)

Access Conditions The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the au...

Repository Name University of Southern California Digital Library

Repository Location USC Digital Library, University of Southern California, University Park Campus, Los Angeles, California 90089, USA