J. D. Whitney on the “ Primordial Fauna” in Nevada. 85 
belong to the genus Paradowides. The class of brachiopods 
is represented in these specimens by two or more genera, all of 
the family of Lingulide. Among these I think that I am able 
to recognize the genera Lingulepis (Lingula) and Obolella. At 
all events, the character of this assemblage of fossils is thor- 
his is an interesting discovery, since it carries the Primordial 
fauna much farther west than it had been found before. The 
most western locality of Potsdam sandstone fossils’ previously 
described, is that in the Big Horn Mountains, at the head of 
the lowest subdivision of the fossiliferous series, and which has 
been found recurring at so many points over the vast area of 
ceous shales; throughout the United States, from New York to 
the Rocky Mountains, in the “Potsdam sandstone, or 1m shales 
we have already a pretty fair representation of almost all the 
groups from the Triassic down to the “ , 
The report of the 40th Parallel Survey will, no doubt, throw a 
great deal of light on the stratigraphy of the various formations 
existing in the Great Basin, of which we now know hardly 
anything more than the bare fact that they do occur in that 
extremely interesting region. 
