1 878.] 
Notices of Books. 
97 
they readily amalgamate with the domestic cattle.” For the 
detailed evidence upon which these inferences are founded we 
must refer to the work itself. This case, joined to that of the 
Leporides , — a confirmatory account of which has lately appeared 
in so hostile a quarter as “ Les Mondes,” — ought, we think, to 
make a clean and final sweep of the so-called physiological test 
of species. It can no longer be safely argued that animals 
which interbreed and produce fertile offspring must be of neces- 
sity specifically identical, nor that those which are morphologic- 
ally distindt must be incapable of producing fruitful descendants. 
By bringing before the world the fadts just referred to Mr. Allen 
has rendered one of the main positions of the old natural history 
simply untenable. 
The extirpation of the bison — or at least its very great reduc- 
tion — is a result which must in the long run have inevitably 
followed upon the cultivation and enclosure of the country. 
But it has unfortunately been carried out in the most wasteful 
and reckless manner, and millions of tons of what might have 
been utilised as human food have been left to rot, or to become 
the prey of wolves and vultures. 
Annual Report of the Board of Regents of the Smithsonian 
Institution, for the Year 1875. Washington : Government 
Printing-Office. 
Amongst the varied and valuable matter contained in this 
volume we notice first a series of publications commenced under 
the title “ Bulletin of the National Museum,” intended to illus- 
trate the colledtions in Natural History and Ethnology belonging 
to the United States. The total number of vertebrate animal 
species found in the Neardtic realm as given, is, we think, 
certainly below the truth, as many fishes must still be un- 
described. The number of insedt species is estimated at 50,000, 
of which 8000 are Coleopterous. In enumerating the main 
zoo-geographical provinces of the world, the “ palgeotropical ” is 
by a curious typographical error transformed into “ palasological.” 
As regards the subdivisions of the Neardtic or North- American 
realm, the author proposes to make in the Eastern region four 
provinces dependent mainly on the isothermal lines — viz., the 
Carolinian, the Alleghanian, the Canadian, and the Hudsonian. 
The Central region is divided merely into two provinces, parted 
by the 100th parallel of longitude. 
Amongst the memoirs forming the bulk of this volume atten- 
tion may be drawn to one by Alphonse de Candolle, translated 
for the Smithsonian Institution, on “The Probable Future of 
the Human Race.” The author’s views may thus be summa? 
VQL, VIII. (N,S.) H 
