44 The Fauna of the Keyser Member of the 



Order TELODESMACEA 



Superfamily CYPRICARDIACEA 

 Family PLEUORPHORIDAE 



Genus CYPRICARDINIA Hall 



Cypricardinia cf. lamellosa Hall 



Plate LXXVIII, Figs. 6, 7 



Cypricardinia lamellosa Hall, 1859, Nat. Hist. N. Y., Pal., vol. iii, p. 266, pi. 

 xlixo, figs, la, 6, c, 1861. 



Description. — "Shell subovoid, gibbous; umbones slightly elevated; 

 anterior extremity abruptly rounded and extending little beyond the beak, 

 somewhat contracted on the base anterior to the middle, with an unde- 

 fined depression extending thence nearly to the umbones; posterior slope 

 prominent, with a scarcely defined ridge; cardinal margin compressed, 

 obliquely subtruncated above and rounded towards the base. Surface 

 marked by strong elevated distant lamella; tlie surface of each one show- 

 ing under a magnifier, distinct radiating striaa, and sometimes another 

 set of striae cancellating the first." Hall, 1859. 



Occurrence. — Helderberg Formation, Keyser Member. Keyser, 

 West Virginia. 



Collection. — U. S. National Museum. 



Class GASTROPODA 



Subclass STREPTON EUR A 

 Order ASPIDOBRANCHI A 



Suborder RHIPIDOGLOSSA 

 Family BELLEROPHONTIDAE 



Genus BELLEROPHON Montfort 



Bellerophon helderbergi^ n. sp. 



Plate LXXIX, Figs. 3, 4 



Description. — Convolute, volutions somewhat flattened dorso-ventrally ; 

 last volution expanding rapidly, aperture expanded. Umbilicus small. 

 Dorsal carina pronounced. Surface ornamentation unknown. 



