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NEW YORK STATE MUSEUM 



been compared with the impression of a colt's foot. R h i p i d o - 

 m e 1 1 a musculosa [fig. 76] is a smaller type, with less 

 marked muscular impressions. L e p tostrophia m a g - 

 nifica [fig. 77], a large nearly flat species, with pronounced 

 divergent muscular impressions and fine radiating striae, is like- 

 wise common, together with several other species of the genus. 

 Spirifer m u r chisoni [fig. 78] and 8 . arenosus [fig. 

 79] are the most characteristic brachiopods of this formation, the 



former distinguished by its broad 

 rounded plications, and smooth 

 fold and sinus, the other by its nu- 

 merous low rounded plications 

 which also extend across the fold 

 and sinus. Internal molds of 

 these two species are character- 

 ized by strong elevations in the 



Fig-. 80 Eatonia peculiar is , . , . _ . , , . . 



rostral cavities, which are dif- 

 ferently marked in the two species, as shown by the illus- 

 trations. Eatonia peculiaris [fig. 80], a small species 

 with a strong anterior deflection, and the surface marked 

 only by fine radiating striae is common. Several huge 

 rhynchonelloids occur of which P 1 e t h o r h y n c h a bar- 

 randei [fig. 81] is the most striking. Others are IMetho- 

 r h y n <• h a p 1 e i o p i e u r a [fig. 82] , 'C a m a r d t o e c h i a 

 oblata [fig. 83] and C. fitch an a [fig. 81]. Lepto- 

 coelia flabellites [fig. 85] is not uncommon and is the 

 only small plicated shell with flat brachial ami moderately convex 

 pedicle valve. Oik 1 of the most characteristic species of this 

 horizon is the large, elongate, robust Rensselaeria 

 o v o i d e s [fig. S6] readily known by its convexity and regular 

 surface striation. With it occurs the smaller, gently convex 

 V e g a I a n 1 oris o v a 1 i s [fig. 87] , in which the surface striae 

 seldom appear. 



The peleeypods are chiefly represented by the large 1 Pterinea 

 text i li s var. a re n a r i a [tig. 88], with its sharp striations; 

 and P t . ge b h a r d i [fig. 89], with flat, rounded plications. 



