KEYIEWS'. 
407 
the same localities j in some districts acquiring more elongated wings, in 
others losing their tails, in others again becoming enlarged or diminished in 
size, and so on. Mr. Meehan has shown the same thing in regard to 
American and European trees. So also has M. Coste shown that English 
oysters, when placed in the Mediterranean, become like the native oysters, 
and soon acquire prominent converging ribs like those of the Mediterranean 
oyster. The same thing may be said of the Cape hunting-dog and the Aard 
wolf, both of which bear a strong external resemblance to the Hyaenas. 
Thus Mr. "Wallace thinks it more probable that the dogs of various regions 
have been thus modified so as to correspond to native foxes, wolves, and 
jackalls, than that they should have been descended from such very distinct 
species, “and have mysteriously acquired the power of breeding together and 
producing fertile offspring, which these species themselves do not possess.” 
In regard to sexual selection also Sir Charles Lyell makes some important 
remarks. Indeed, in this respect he seems almost to have accepted Mr. 
Darwin’s ideas. Thus he says that a considerable number of the most 
striking external characters of animals are confined to one sex, such as the 
horns and canine tusks often found in the males only of quadrupeds, the 
ornamental plumes, gay colours, and musical voices of male birds, and the 
varied horns and excrescences of male insects. “ Mr. Darwin has shown 
that these characters are often useful to the males in their struggle for 
mates. Some actually fight together, and the possessor of the greatest 
strength and the best weapons will be the parent of the next generation ; 
others captivate the females by their beauty or their song, and these, by 
obtaining the earliest and most vigorous mates, will have the most nume- 
rous and healthy offspring. Favoured individuals will thus have an advan- 
tage in the transmission of these peculiarities; and in this manner Mr. 
Darwin believes have been produced the noble antlers of the stag, the sharp 
spurs of the cock, and the gorgeous train of the bird of Paradise. Sexual 
selection thus becomes an important supplement to natural selection, and 
may enable us to account for structures which could not be explained by 
the mere ‘ preservation of favourable variations in the struggle for life.’ ” 
There is one more point to which we would refer ere we close our notice of 
this remarkable work. It has reference especially to the Darwinian view 
of our origin from the lower animals, and it certainly bears very strongly 
upon it. To a rational mind there seems to be very little difficulty in 
believing that man has proceeded from some of the Quadrumana. But 
to those who are differently constituted it is otherwise, and hence every 
argument in favour of the view is necessary to be brought forward. The 
present argument is comparatively a recent one, and assuredly it is very 
forcible. It is as to the resemblance between the humerus of prehistoric 
man and that of the Quadrumana. For example, in the latter and the 
carnivora there is a passage near the lower end of the humerus, called the 
supra-condyloid foramen, through which the great nerve of the fore-limb 
passes and often the great artery. Now occasionally this foramen occurs in 
man with the nerve passing through £it, and it is remarkable that the per- 
centage of the occurrence of this variation is greater in ancient than in 
modern races in the proportion of nearly 30 to 1. This has been ascertained 
by the examination of large numbers of arm-bones of the Bronze and Rein- 
