200 PALiEONTOLOGY. 



Texas, &c.). The remarkable form there described and figured, under the 

 name PterocephaUa Sanctisaha, finds a close representative in the one here 

 given as Pteroceplialus latkeps, and shows the propriety of the generic separa- 

 tion, while the form characterized by the "slipper- shaped" glabella of Dr. 

 Owen shows not only the wide geographical distribution of this peculiar 

 type, which is common in the Wisconsin beds, and. largely prevails in the 

 White Pine, Eureka, and Schell Creek locahties, and also occurs in the San 

 Saba district, but also its value as a generic type, for which Dr. Owen pro- 

 posed the name CrepicepJialus, which may with propriety, we think, be 

 retained for this widely-distributed group. The extensive geographical 

 range of these peculiar and marked generic forms, through the western 

 countries, is a point of great interest, and a feature that will undoubtedly be 

 of much service in the future study of the formations over these as yet 

 imperfectly-explored regions, as, from their strongly-marked character, they 

 will be readily recognized, and serve as reliable guides in tracing out and 

 locating, stratigrapliically, the formations wherever they may be met with. 



Besides the above, the genera Dikellocephalus, Ptychaspis, Chariocephalus, 

 and Agnostus have been recognized in one or more species each. The Brachi- 

 opodous fauna of these localities is quite meager, both as regards species 

 and individuals, and affords but imperfect means for comparison with that 

 of other localities. The genus Lingulepis has been fully recognized, and a 

 species, apparently referable to the genus Oholella, also occm-s at Eureka, 

 together with a minute species of Kutorgina. No other forms of life have 

 as yet been noticed among the collections from rocks of this age within the 

 region covered by the Survey. 



A few very interesting species of Trilobites and other forms have been 

 given from the collections from the base of Ute Peak, Wahsatch Range, 

 Utah, which, from the evidence furnished by the Brachiopodous and 

 Molluscan fiiuna, have been referred to the age of the Quebec group, 

 together with other beds at White Pine, Nevada, and East Canon, Oquirrh 

 Mountains, Utah. 



The Devonian fonnations are represented in a few localities; among 

 the most interesting of which may be mentioned that of Treasure Hill, and 

 the black slates near Eberhardt Mill, White Pine Mountains, Nevada. The 



