GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 147 



Stenoschisma altiplicatum [fig. 52] is readily dis- 

 tinguished by the abrupt anterior emargination due to the deep 

 folding sinus. It is, however, not so readily distinguished from 

 Stenoschisma f o r m o s u m [fig. 53], which is a broader 

 and less triangular shell. 



E a t o n i a in e d i a 1 i s [fig. 54] is a rhynchonelloid with an 

 abrupt and marked anterior deflection, and rounded plications 

 chiefly at the anterior margin. 



Among the smooth brachiopods are Meristella laevis 

 [fig. 55], M. a rcuata [fig. 56 and 56a] and M. princeps 



Fig. 55 Meristella laevis 



[fig. 57], which are readily distinguished from one another by 

 their form and proportion and from the other brachiopods of this 

 horizon by the absence of surface striae or plicat ions. 



A try pa reticularis [fig. 38] is abundant in this as in 

 the other formations. 



A number of pelecypods occur in this horizon, but on the 

 whole they are not common or well preserved. One of the most 

 readily recognized is A c t in apt eri a textilis [fig. 58], 

 which is very oblique, with a strong posterior wing, and sharp 

 radiating striae cancellated by concentric lines. A. securi- 



