640 REVIEWS. 
formations separate into five or six; and Stansbury mentions one 
locality where there are ten or twelve of them. In the Missouri 
Valley and along the eastern slope generally, the terraces vary 
much in height and importance. 
The distant hills are composed of the yellow marl or loess, and 
the surface has been weathered into the rounded, conical hills. 
This portion is often covered with the drift or stray rocks, or what 
I have called in a former report the erratic block deposit. Qn the 
terraces these erratic masses are scarcely ever found, and in the 
broad bottoms of the Missouri River seldom if ever. This fact 
strengthens the opinion that the terraces are really one of the 
latest features, and that they were formed during the drainage of ` 
somewhat to the formation of the terraces, but I am inclined to 
believe that the drainage or the contraction of the waters is the 
main cause. This is an important point, and I hope hereafter to 
to Mexico are gashed with gullies or canons, many of which are 
Any one with geological proclivities about to take a trip across 
the continent over the Pacific Railroad should by all means read 
this interesting sketch of the country between Omaha and Salt 
ake. 
The third part contains a report by Prof. C. Thomas on the ag- 
ticulture of the Territory, with notes on the grasshoppers, espec- 
ially the Western Locust (Caloptenus spretus.) 
Part IV. contains a preliminary paleontological report by Prof. 
F. B. Meek, with reports on the Tertiary coals of the West, by 
James T. Hodge; on the ancient lakes of Western America, their 
deposits and drainage, by Prof. J. S. Newberry (which will be 
