PALEOZOIC SECTION IN CENTRAL NEVADA. 
The geologic portion of the accompanying section is taken from the 
“Abstract of Report on the Geology of the Eureka District, Nevada, by 
Arnold Hague,” contained in the Third Annual Report of the Director of 
the United States Geological Survey, p. 253. It is introduced to enable 
the student at a glance to locate in the geologic section the position of any 
portion of the Paleozoic fauna described in the preceding list. 
All of the Cambrian fauna is included under the head of ‘“ Prospect 
Mountain Group,” in the systematic list. 
The Lower Silurian includes the fauna of the Pogonip limestone and 
the base of the Lone Mountain limestone, only two or three species of corals 
indicating the presence of an Upper Silurian fauna. 
The Devonian limestones are highly fossiliferous throughout. The 
fauna is best preserved within 500 feet of the base and summit, the massive 
beds of the central portions yielding but very few good specimens. 
The White Pine shales in the Eureka District gave but two identified 
species and fragments of ten others referred to genera. In the White Pine 
District the fauna is scattered through the shale and embraces fourteen 
named species and eleven referred to genera. 
The large fauna of the Lower Carboniferous occurs within a range of 
500 feet above the summit of the Diamond Peak quartzite. Only 24 of the 
132 species of the Carboniferous fauna occur above that horizon, and of 
these 10 are present in the lower beds. 
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