GASTROPODA— -EUOMPHALIDJE. 



663 



186. E. distans Bill. (Fig. 915.) Ordovicic. 



A loose, regularly spiral coil of two or more slender whorls, 

 separated by about once and a half their diameter ; upper side 

 carinate, others rounded. 



Quebec group (Beekmantown) of Newfoundland. 



Fig. 915. Eccyliomphalus distans, lower side. (After Billings.) 



187. E. undulatus Hall. (Fig. 916.) Ordovicic. 



Whorls more distant and more rapidly increasing than in the 

 preceding ; section subtriangular or ovate-triangular, a broad sinus 

 in the upper lip. Surface often indented from attachment of 

 foreign objects. Inner whorls often cut off by imperforate septa. 



Stones River of Minnesota, Wisconsin, Illinois, and Tennessee. 



Fig. 916. Eccyliomphahis undu- 

 latus. (After Ulrich and Scof., Pal. 

 Minn. ) 



Fig. 917. Eccyliomphalus triangulus, in- 

 ternal mold, showing the collar but faintly. 

 (After Ulrich, Pal. Minn.) 



188. E. triangulus Whitf. (Fig. 917.) Ordovicic. 



Very loose coils, one and one half volutions rather rapidly en- 

 larging ; keel sharp and prominent, often forming a collar, upper 



