352 



Described page 311, and represented by Figs. 4 to 6, Plate XVII. From 

 the Carboniferous formation of Kansas, Nebraska, and Illinois. 



Cestra.ciontid,e. 



ACRODUS. 



ACKODUS HUMILIS. 



Leidy : Pr. Ac. Nat. Sc. 1872, 1G3. 

 Described page 300, and represented by Fig. 5, Plate XXXVII. From 



the Cretaceous limestone of New Jersey. 



Aceodus Emmonsi. 



Leidy : Pr. Ac. Nat. Sc. 1872, 163. 



Acrodus. Emmons: North Carolina Geol. Sur. 1858, 244, Fig. 97. 



Attributed by Professor Emmons to the Miocene of North" Carolina. 



PTYCHODUS. 



Ptychodus Mortoni. 



Agassiz: Poissons Fossiles ILT, 1833-'43, 158, Tab. 25, Figs. 1 to 3; copied in 



Figs. 773, 773«, of Dana's Manual of Geology. Leidy : Pr. Ac. Nat. Sc. 1808, 



205. 

 Palate-bone of a fish 1 Morton : Syn. Org. Bern. Cret. Group, 1834, Plate XVIII, 



Figs. 1, 2. 



Described page"" 295, "and represented by Figs. 1 to 14, Plate XVIII 

 From the Cretaceous of Kansas, Mississippi, and Alabama. 



Ptychodus. occidentalis. 



Leidy : Pr. Ac. Nat. Sc. 1868, 207. 

 Described page 298, and represented by Figs. 7, 8, Plate XVII, and Figs. 

 15 to 18, Plate XVIII. From the Cretaceous of Kansas. 



Ptychodus Whippleyi. 



Marcou : Geology North America, 1858, 33, Plate I, Fig. 4. 

 Described page 300, and represented by Figs. 19, 20, Plate XVIII. 

 From the Cretaceous of Texas. 



Ptychodus polygyeus. 



Agassiz : Poissons Fossiles III, 1833-'43, 156. Dixon : Geol. Sussex, 1850, 363. 

 Gibbes: Jonr. Ac. Nat. Sc. 1849, 299, Plate XLII, Figs. 5, 6. Leidy: Pr. Ac. 

 Nat. Sc. 1868, 208. 



From the Cretaceous of Alabama. 



