REVIEWS. 
HE GEOLOGY oF Wyomrna.* — The first part contains a geo- 
logical itinerary, while the second part is more general in its na- 
ture, containing chapters giving a general view of the geology of 
the Missouri Valley, of the region between Omaha and Cheyenne, 
the route over the first range, the Laramie Plains and westward to 
Bear River, and onward to the Great Salt Lake Valley, closing 
with a chapter giving a general review of the geology of the 
country from Omaha to Salt Lake Valley, and a final chapter on 
the mines, ete. 
Prof. Hayden’s explorations are extended over an immense ex- 
tent of country, and while the work is our only authoritative guide 
to the geological and agricultural capabilities of this important 
area, even these preliminary reports throw a flood of light on the 
geological history not only of the American Continent, but we 
may venture to add that of the globe and the succession of life on 
its surface. In illustration we quote as follows :— 
“ That there is a connection Sinha all the coal beds of the far 
West I firmly believe, and I am convinced that in due time that 
relation will be worked pond Has the links in the chain of evidence 
joined together. That some of the older beds may be of upper 
Cretaceous age ‘Tam eens to believe, yet until much clearer 
light is thrown upon their origin than any we have yet secured, I 
. shall regard them as belonging to my ie a series or beds of 
passage e betwee en the true Cretaceous and the lary. 
the large’ collections of fossil plants fea the West n 
in ne enei of Dr. Newberry are carefully studied, we shal 
have a much better basis upon which to rest a conclusion. will 
seen at once that one of the most important Urobia H in the 
geology of the West awaits solution, in detecting, without a doubt, 
the age of the coal series of the West, and the exact = of de- 
mareation between the Cretaceous and. Tertiary peri 
he study of this question shows the importance of ‘the contin- 
o dt 
aed ac 
Neither can we place too rigid reliance on the teachings of the 
* Preliminary Report of the U. S. Geological Survey of Wyoming, and portions of 
contiguous territories (being a second annual report of progress). By F. V. Hayden, 
` U.S. Geologist. Washington, 1871. 8vo, pp. 511. (637) 
