^ MAMMALIA. 
2 
colour and other ornaments are concerned, has prevailed far more 
extensively with Mammals than with Birds j but in regard to 
weapons, these have often been transmitted either exclusively or 
in a much higher degree to the males than to the females. 
Their absence in the female can be accounted for only by the 
form of inheritance which has prevailed. The contest between 
the individuals of the same sex, whether peaceful or bloody, has, 
with the rarest exceptions, been confined to the males ; so that 
these have been modified through sexual selection, either for 
fighting with each other or for alluring the opposite sex, far 
more commonly than the females. 
A large portion of the animal kingdom is passed in review, as 
regards sexual differences and the means by which this dif- 
ferentiation has been produced. This part abounds in matter of 
interest ; and we may well believe that it required many years to 
collect these materials. The account of the sexual differences in 
Mammals occupies pages 239-315 of the second volume, and is 
illustrated by numerous excellent woodcuts. 
Mivart, St. G. On the Genesis of Species. London: 1871. 
16mo, pp. 296, with woodcuts. 
Witli this work before us we must again express our regret 
that the ^Zoological Record^ is not headed by an abstract of 
the literature of General Zoology ; and we refer to this work 
here only because we have previously treated of similar pub- 
lications at the same place. We believe it is generally ac- 
knowledged that Mr. Mivart has brought forward the most 
weighty arguments against the views started and developed by 
Mr. Darwin. Without controverting the doctrine of evolution, 
he regards natural and sexual selection as quite incompetent to 
account for specific modification. He maintains that species 
have been evolved by ordinary natural laws (for the most part 
unknown), controlled by the subordinate action of natural selec- 
tion — and that there is and can be absolutely nothing in phy- 
sical science which forbids us to regard those natural laws as 
acting with the Divine concurrence, and in obedience to a crea- 
tive fiat originally imposed on the primuival Cosmos. 
Zelebou, J. Reisc der osterreichiseben Rregatto ^Novara^ um 
dieErde. Zoologischer Theil, i. Saugethiere. Wien : 1869. 
4to, pp. 44, with 3 plates. 
The author of this part has confined himself to an enumeration 
of the species collected during the expedition, and to descriptions 
of three species considered to be new. 
Milne-Edwards, H. & a. Recherches pour servir k Thistoire 
naturelle des Mammiferes. Paris : 4to. 
See Zool. Record, v. p. 3, and vi. p. 2. Four more parts 
(nos. 6-9, to p, 208) have reached this country, containing the 
