342 PROCEEDINGS OF THE ACADEMY OP 



below the tapering vertebral column. It is broken off in the t3'pe, 

 but in anotlier specimen is evidently quite elongate, and of the 

 protocercal or isocercal type. There are two huge oval gular 

 plates, as I suppose tliem to be, which are well separated from each 

 other and of a broadlv oval form. 



In another specimen the dentition of one of the jaws is exhibited 

 as a double series of small, subequal, subconical crowns. In still 

 another tlie pectoral fin is displayed as broadl}' and obtusely 

 lobate. Whether these all belong to the same genus may be un- 

 certain, but their resemblance is very close. Size not large. The 

 genus is evidently allied to the Gyclodipieridse. 



CONCHIOPSIS FILIFERUS, Cope. 



About twelve rows of scales between the dorsal and ventral fins, 

 which stand opposed to each other, and half way between the gular 

 shields and the line of the equall}" opposite second dorsal and ven- 

 tral. Sculpture of the gular plates, a longitudinal thread-like rib- 

 bing parallel to the inner borders. 



M. 



Length from gular plates to anal fin 057 



Depth at D. 1 088 



" D. 2 02G 



The type specimen was obtained and presented to me by my 

 friend "William Kite. 



CONCHIOPSIS ANGULIFERTJS, Cope. 



Established on a specimen of larger size than the last species, 

 but in which the scales are similar and therefore relativel}'^ smaller. 

 The gular plates have a band of delicate ridges around their outer 

 marsins, and numerous ridges which diverge from the middle of 

 the scale to tlie band. These ridges are undulate. Posterior to 

 the plates on each side is a long incurved bone, perhaps the man- 

 dibular angle. The pectoral fin contains about thirteen radii. 

 Prof. Newberry's collection. 



CONCHIOPSIS EXANTHEMATICUS, Cope. 



Estaltlished on a cranium entirely preserved as to its outline, 

 with adjaeent portion of space for chorda dorsalis and osseous 

 ribs. The head is covered with thin scuta, Avhich are very faintly 

 sculptured with a few raised lines. The gular shields are oval and 

 sculptured with elevated points, producing a weakly rugose sur- 



