NOTICE OF SOME REMAINS OF FISHES FROM THE CARBONIF- 

 EROUS FORMATIONS OF KANSAS. 



The remains described below were obtained by Dr. F. V. Hayden and 

 Mr. F. B. Meek in the summer of 1858, and were originally noticed by the 

 writer in the Proceedings of the Academy of Natural Sciences of Philadel- 

 phia in January, 1859. 



Plagiostomi. 



CLADODUS. 



Cladodus occidentalis. 



The extinct genus of cartilaginous fishes, Cladodus, was first characterized 

 by Agassiz from isolated teeth from the Coal-formation of Europe. A 

 species of the same genus is indicated by a fragment of a tooth discovered 

 by Messrs. Hayden and Meek in the upper Coal-measures of Manhattan 

 Kansas. 



The specimen has lost one-half its base, a large portion of its principal 

 cusp, and the points of the lateral cusps, but sufficient remains to give us a 

 correct idea of the form of the perfect tooth, as represented in Figs. 4 to 6, 

 Plate XVII. 



The base of the tooth is oblong in outline, with the inner border some- 

 what angular and the outer one concave. Its upper inner surface slopes from 

 the cusps, and near its margin, a short distance from the extremities, supports 

 a pair of oval tubercles. Similar protuberances occupy a position beneath 

 the base externally. 



The median or principal cusp of the tooth is elongated demiconical, with 

 acute lateral edges. The inner convex surface of the cusp at its base exhibits 

 sharp, oblique folds or strise, as represented in Fig. 4. The outer less convex 

 or nearly flat surface is smooth, except a few vertical wrinkles at its base. 



The lateral denticles on each side of the principal cusp are two, of which 

 the outer is the larger. 



