﻿34 Bulletin 20 112 



plications, with one or two finer plications occupying the interven- 

 ing spaces between the stronger ribs. Fine concentric striae cross 

 the plications. 



This fossil is known from a single left valve. 



Locality. — Paradise P. O., Utah. 



Actinopteria (?) sp. 



A fragment of the cast of a left valve shows a shell with strong 

 equal radiating striae crossed by fine concentric striae. Posterior 

 ear with deeply concave margin. 



Locality. — Paradise P. O., Utah. 



GASTROPODA 



Platyceras sp. 

 A small fragmentary specimen of Platyceras marked with fine 

 transverse striae occurs in the collection from Princeton, Mont. 



Naticopsis sp. 



Two casts of a shell having a general resemblance to N. levis 

 occur in the collection. The material is too poor to permit 

 specific determination. 



Locality. — Logan, Utah. 



Loxonema approximatum Walcott? 



The collection contains two poorly preserved specimens in 

 which the surface characters are not preserved, but which have a 

 general resemblance to this species and may be identical with it. 



Locality. — Princeton, Montana. 



Tropidocyclas sp. 

 PI. IV fig. 6. 

 A single fragmentary specimen of a strongly compressed 

 discoidal form is present in the collection. The surface is marked 

 by strong riblike striae, rather widely spaced, which make a sharp 

 retral curve from the margin of the umbilicus to the periphery. 

 Locality. — Logan, Utah. 



