102 Recent Literature. [ February, 
size, which recent naturalists have developed and formulated. I 
suspect that Mr. Allen allowed himself to become slightly quiz- 
zical at the close of his critique ; but I shall take him at his word, 
and reply seriously. I do not find that Bartram presents anything ` 
but a statement of fact of the smaller size of Floridan animals as 
compared with those from Pennsylvania; to do which, nothing 
but a tape-line, or, failing that useful article, a good pair of eyes 
and fair memory, were requisite. Whereas, in treating of the 
same important subject himself, Mr. Allen has been prominent 
among those who have generalized from the facts to broad con- 
clusions; and in so doing has displayed inherent powers of mind 
which, coupled with extensive and varied acquirements, have won 
for him the high position he now holds among American natural- 
ists. . 
RECENT LITERATURE. 
POWELL’S EXPLORATION or THE CoLorapo.!— The first part of 
this volume contains the personal narrative by Major Powell of his peril- 
ous and successful exploration of the most wonderful river-gorge in the 
world. The second part, containing his observations on the physical 
features of the Valley of the Colorado, will be noticed in a fature number 
of this journal. 
The narrative is one of the most thrilling records of personal advent- 
ure we have ever read; the interest of the reader is intense from the 
first to the last page, the story being told in a modest, unpretending way, 
so that the dangers do not seem exaggerated, and the impression pro- 
duced by the rare exhibition of courage and endurance is not lessened by 
any straining for effect in the words of the narrator. 
The cañon of the Colorado is over a thousand miles long, and at one 
point over a mile (6200 feet) in depth. This deep cut is broken at inter- 
vals by lateral cafions, where branches, such as the Grand, Yampa, Vir- 
gin, Kanab, and others, enter the main stream. An idea of the grand- 
eur of these dark, solitary gorges, with vertical sides often nearly a mile 
high, and with pinnacles and towers overhanging the river winding like 
a silvery thread below, may be gained by a glance at the figures of Mu- 
koon-tu-weap Cañon, of a cañon in Escalante Basin (Fig. 5.), but espe- 
cially of the Grand Cañon.. The bird’s-eye view of the Terrace Cañons 
(Fig. 6) represents the relations of these cafions to the surrounding 
country. 
1 Exploration of the Colorado River of the West and its Tributaries. Explored in 
1869, 1870, 1871, and 1872, under the Direction of the Secretary of the Smithsonian 
Institution. By J. W, Power. Washington, D. C. 4to, pp. 291. With Maps and 
Illustrations, 
