450 Marsh — JSeic lieptiir* from the Laramie Formation. 



Coniophis jjrecedens, gen. et sp. nov. 



The earliest serpents hitherto known in this country are 

 included in the genera Titanophis {Dinophis) from the marine 

 Eocene of New Jerse} r , and JBoavus from the fresh- water 

 Dinoceras and Coryphodon beds of the West, both described 

 by the writer.* None have hitherto been found in the 

 American Cretaceous, and but one species is known from 

 Europe.f The type specimen of the present genus and»species 

 is the vertebra represented below in figure 1. Several others 

 were found at the same locality, but may not pertain to this 

 individual. 



Figure 1. — Vertebra of Coniophis precedent, Marsh. 

 «, natural size ; b, c, d, e, three times natural size. 



In the type specimen figured above, the zygosphene articu- 

 lation is fully developed, and all the characteristic Ophidian 

 features are distinctly shown. The nearer affinities of the 

 genus will be discussed in a later communication. All the 

 known remains of the species are from the Ceratops beds of 

 Wyoming. 



Ohamops segnis, gen. et sp. nov. 



The type specimen of the present genus is the maxillary 

 bone with teeth represented in figures 2 and 3 below. Various 

 other parts of the skull and skeleton have been found at dif- 

 ferent localities in the same horizon, but it is not certain that 

 they pertain to the same species. Dentary bones with pre- 

 cisely similar teeth, and corresponding in size with the jaws 

 figured, have been secured, and there can be little doubt of 

 their identity. Among the other portions of the skull obtained 

 is the upper part of the cranium. This has the surface very 

 rugose, and is perforated by a large parietal foramen. 



*This Journal, vol. xlviii, p. 397, November, 1869; and vol. i, p. 322, May, 1871. 

 ■(■ Sauvage, Compte Rendu, t. xci, p. 671, 1880. 



