GEOLOGY. 775 
reduced and rudimental, leaving a parallel two-crested tooth, ap- 
proaching a Tapia or Dinotherium. There were probably tusks in 
the lower jaw. 
The animal was about the size of the rhinoceros and constituted 
another addition to the well-armed ungulates of the Wyoming 
Eocene. The transitional forms seen in its tooth structure consti- 
tute a point of especial interest. 
BE A a ier) ee eet. ae ps S 
We E E ARSE S ed es yaa ROE ENA E EAE TEE 
Tus Fiısn-sEps or Ostno, Nevapa.— Investigations into the 
geology of Nevada, conducted during the present season by Prof. 
Cope, of Dr. Hayden’s Geological Survey, have resulted in the dis- 
covery of an extensive lake basin, which was filled with fresh water 
during some of the Tertiary periods. Its deposits were thrown 
into lines of upheaval by the elevation of the Ruby Mountain 
Range, and the North Humboldt River traverses the deepest por- 
tion of the old lake. The Humboldt River Sink is its last rem- 
nant, bearing the same relation to the Humboldt River as the 
Great Salt Lake to the Bear River of Utah. 
The strata are in many places exceedingly thin and paper-like, 
resembling the braun kohle of Prussia. Two seams of a cannel- 
like coal, of about three feet each in thickness, have been exposed 
by excavations. This is the most western locality for coal east 
of the Sierra Nevada. The shales contain great numbers of fos- 
sil fishes, insects, plants, ete. The fishes are all of fresh water 
types; one of them is related to the existing type of Catostomide 
(sucker), and has been called Amyzon mentale. It is a sucker 
with the sucking mouth “left out ;” that part resembling its proto- 
type in ordinary fishes. Another species is related to the “ Bull- 
minnows” (Cyprinodontide), but differs from known genera in 
having bristle-like bodies instead of ordinary scales. It is called 
Trichophanes hians. The insects are chiefly mosquitoes and long- 
legged flies (Tipula). ` r 
The age of the beds was thought to be Green River or Lower 
Eocene. : 
On the northern ridge bordering the Humboldt valley, Nevada, 
there are completely opalized portions of trunks of trees which 
were at least five feet in diameter. The ground is strewn with 
black, yellow, red, purple or porcelain-white colored fragments. 
The age of the remains is probably Tertiary and the trees are 
mostly dicotyledons. 
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EEE TEE AE pee E E N a AT A S. 
