432 GEOLOGICAL SURVEY OF THE TERRITORIES. 



VIIL— RECENT REPTILES AND FISHES. 



EEPOBT ON THE EEPTILES AND FISHES OBTAINED BY 

 THE NATURALISTS OF THE EXPEDITION. 



By E. D. Cope, A. M. 



Twenty- two species of fishes and eight of reptiles are embraced in 

 this collection. Among these the principal interest attaches to the fish- 

 fauna of the Colorado Biver of the West, and its system. Isolated as 

 are its waters from the "systems of the Columbia on the north, of the 

 Platte on the east, of the Bio Grande on the southeast, and of the Pa- 

 cific Coast streams on the west, an inquiry into the character of its fauna 

 becomes desirable. This-has been entered on with much success by our 

 distinguished ichthyologists, Messrs. Baird and Girard, who have deter- 

 mined the existence of at least one type as peculiar to it ; I allude to 

 the genus or group Gila. They have also shown that nearly, if not all, 

 of the species belonging to it differ from those of the other basins — 

 a conclusion which the collections of Dr. Hayden confirm. The num- 

 ber of species from the heads of the Colorado included in the present 

 collection numbers 13, none of which have been found in other waters, 

 if we include in this basin those which empty into the lakes of Utah — 

 and of which five are new to science. 



Beyond the possession of peculiar species and one peculiar genus this 

 river basin does not differ from others except in what it lacks. This 

 want of forms may be owing to the poverty of our collections, or 

 to their real absence. It is enough to mention Siluroids, Hyodon, 

 Esox, Lepidosteus, Amia, and Physoclysti, in general, to express the im- 

 perfection of our knowledge and the probability that, when examined, 

 an interesting fauna! combination may be discovered. Not the least in- 

 teresting fact is the occurrence of a Coregonus in the Green Biver and 

 other upper waters of the basin. 



The other fishes obtained by Dr. Hayden are from the upper tributa- 

 ries of the Platte. As pertaining to the same great Missouri drainage 

 area, a few species from the neighborhood of St. Joseph, Northwestern 

 Missouri, are added. These were submitted to me by Dr. William Stimp- 

 son, secretary of the Chicago Academy of Sciences. 



BEPTILIA. 



Caudisona confltjenta, Say, (Crotalus.) — Utah, Colorado, Wyo- 

 ming, &c. 



Heterodon nasicus, Baird and Girard. — Head- waters of the Platte. 



Eut^nia paretalis, Say, (Tropidonotus, Halb.) — Head-waters of the 

 Platte. 



Eutjenia vagrans, Baird and Girard. — Utah, Wyoming, and Col- 

 orado. 



Holbrooria maculata, Baird and Girard. — Head-waters of the 

 Platte. 



Phrtxosoma dottglassii, Bell. — Head- waters of the Platte. 



BATEACHIA. 

 Bana halecina, Bosc— Common along all the streams. 



