232 



Cyrtoceras VaJlandigliami — Bcyricliia Duryi. 



Cyrtoceras Vallandighami — (S. A. Miller). 



Fig. 23— Cyrtoceras Vallandighavvi. 



Shell rather stronglj^ curved. Section nearly circular, the dorso- 

 ventral diameter a little longer than the lateral, occasioned by an oval 

 prolongation for the siphuncle on the dorsal margin. 



Surface smooth so far as observed. Siphuncle small and in contact 

 with the shell on the dorsal side. 



The specimen figured has 19 septa ; length in a direct line on the 

 dorsal side, |§ inch ; ventral side, f-§ inch ; diameter, large end, from 

 ventral to dorsal side, f i inch ; small end, i^ inch ; length of septa on 

 the dorsal side, at large end, -g^ inch ; small end, -^-^ inch. 



The chamber of habitation has been broken from the large end, and 

 has not been observed in other specimens. 



The specific name is given in honor of Mr. George Vallandigham, of 

 Cincinnati, an active collector, who found the specimen near the top of 

 the hills at Cincinnati, Other collectors have found fragments and 

 inferior specimens, but it may be regarded as an extremely rare 

 sjjecies. 



Beyrichia Duryi — (S. A. Miller). 



. Fig. 2i— Beyrichia Duryi. Magnified 

 25 diameters. 



Fig. 25 — Interior of left valve, 

 nified 25 diameters. 



Mag- 



Shell small, semi-elliptical, rounded at both ends, and slightly trun- 

 cated obliquely at the dorsal angles. More convex anteriorly than 

 i posteriorly. A single depression, slightly arcuate, extends from the 

 dorsal margin two thirds across the shell, situated about one third the 

 length from the anterior end. The outer edge of the border around 

 the basal margin is notched or finely crenuiated. This is plainly 

 visible in an entire specimen. 



