CENTEAL AND EASTEEN NEVADA. 41 7 



Many of the beds are quite rich in fossils, but the specimens obtained are 

 either not sufficiently well preserved for determination, or the association of 

 species is such that the exact age of the formation may be doubtful. The 

 following forms occur : Athyris, Pleurotomaria, Ariculojpecten, Naiadites, Le- 

 corhynchus. Professor Meek, speaking of the collection of specimens from 

 these beds, says: 



"The Lecorhynchus, if it really belongs to that genus, would, judging 

 from the known position in New York of the species, rather point to the De- 

 vonian. The Ariculopecten and Naiadites however, would, on the other hand, 

 furnish very strong evidence that these dark beds belong to the Carboniferous." 



The sandstone beds are very poor in fossil remains. In the lower strata, 

 next the shale, are found a few impressions of leaves of the genus Lepidoden- 

 dron, and with them, although rare, the genus Cordaites; these constitute, 

 with the exception of some indeterminable fragments of Crinoid s>te.mB, all the 

 remains yet found. 



The Carboniferous limestone is highly fossiliferous, and rich in remains 

 of well-marked types, nearly all the species being identical with well known 

 European or American Carboniferous forms. The following are among the 

 most characteristic species: Productus longispinus ; P. semireticulatus ; P.sca- 

 briculus; Spirifer earner atus. 



Upon the map of the White Pine District, on Atlas-Plate 14, the non- 

 fossiliferous, calcareous shale and the siliceous limestone are colored brown, 

 as belonging to the Devonian. The evidence in regard to the age of the argil- 

 laceous shale and sandstone points so strongly to the Carboniferous that they 

 are both colored blue, as belonging to that period. 



The accompanying sections, Plate XXVIII, show the relation of Treasure 

 Hill to the surrounding country, and, although drawn with a vertical scale 

 greatly exaggerated over the horizontal, serve to point out the relation and 

 position of the different formations. They are cut on an east and west line. 

 No. 1 crosses the summit of the Blue Ridge ; No. 2 crosses Telegraph Peak ; 

 No. 3 crosses the southern end of Treasure Peak and Pogonip Flat. 



All observations of the mining explorations and developments of the ore- 

 bodies show that, in their geological position, the metalliferous deposits are 

 53 



