choice on the part of the female in the highest degree incredible.

Similarly with the higher classes, i.e. Fishes, Reptiles, and Beasts, we have descriptions and representations of a number of sexual peculiarities, but no evidence whatever that such characters are due to female selection. Often we have statements which conflict strongly with a belief in any such action. Thus, e. g., Mr. Darwin quotes Mr. R. Buist, Superintendent of Fisheries, as saying that male salmon

Are constantly fighting and tearing each other on the spawningbeds, and many so injure each other as to cause the death of numbers, many being seen swimming near the banks of the river in a state of exhaustion, and apparently in a dying state.' . . The keeper of Stormontfield found in the northern Tyne about 300 dead salmon, all of which with one exception were males; and he was convinced that they had lost their lives by fighting.'-vol. ii. p. 3.

The female's choice must here be much limited, and the only kind of sexual selection which can operate is that first kind, determined by combat, which, we before observed, must rather be ranked as a kind of natural selection.' Even with regard to this, however, we may well hesitate, when Mr. Darwin tells us, as he does, that seeing the habitual contests of the males, it is surprising that they have not generally become, through the effects of sexual selection, larger and stronger than the females ;' and this the more as 'the males suffer from their small size,' being liable to be devoured by the females of their own species (vol. ii. p. 7). The cases cited by our Author with regard to fishes, do not even tend to prove the existence of sexual selection, and the same may be said as to the numerous details given by him about Reptiles and Amphibians. Nay, rather the facts are hostile to his views. Thus, he says himself, 'It is surprising that frogs and toads should not have acquired more strongly-marked sexual differences; for though cold-blooded, their passions are strong' (vol. ii. p. 26). But he cites a fact, than which it would be difficult to find one less favourable to his cause. He adds: Dr. Günther informs me that he has several times found an unfortunate female toad dead and smothered from having been so closely embraced by three or four males.' If female selection was difficult in the case of the female salmon, it must be admitted to have been singularly infelicitous to the female toad.

We will now notice some facts brought forward by Mr. Darwin with regard to beasts. And first, as to the existence of choice on the part of the females, it may be noted that 'Mr. Bienkiron, the greatest breeder of race-horses in the world, says

that

that stallions are so frequently capricious in their choice, rejecting one mare and without any apparent cause taking to another, that various artifices have to be habitually used.' He has never known a mare to reject a horse;' though this has occurred in Mr. Wright's stable.

Some of the most marked sexual characters found amongst mammals, are those which exist in apes. These are abundantly noticed by Mr. Darwin, but his treatment of them seems to show his inability to bring them within the scope of his theory.

It is well known that certain apes are distinguished by the lively colours or peculiarities as to hair possessed by the males, while it is also notorious that their vastly superior strength of body and length of fang, would render resistance on the part of the female difficult and perilous, even were we to adopt the utterly gratuitous supposition, that at seasons of sexual excitement the female shows any disposition to coyness. Mr. Darwin has no facts to bring forward to prove the exercise of any choice on the part of female apes, but gives in support of his views the following remarkable passage:

Must we attribute to mere purposeless variability in the male all these appendages of hair and skin? It cannot be denied that this is possible; for, with many domesticated quadrupeds, certain characters, apparently not derived through reversion from any wild parent-form, have appeared in, and are confined to, the males, or are more largely developed in them than in the females, for instance, the hump in the male zebu-cattle of India, the tail in fat-tailed rams, the arched outline of the forehead in the males of several breeds of sheep, the mane in the ram of an African breed, and, lastly, the mane, long hairs on the hinder legs, and the dewlap in the male alone of the Berbura goat.'— vol. ii. p. 284.

If these are due, as is probable, to simple variability, then, he adds,―

It would appear reasonable to extend the same view to the many analogous characters occurring in animals under a state of nature. Nevertheless I cannot persuade myself that this view is applicable in many cases, as in that of the extraordinary development of hair on the throat and fore-legs of the male Ammotragus, or of the immense beard of the Pithecia (monkey).'-vol. ii. p. 285.

But one naturally asks, Why not? Mr. Darwin gives no reason (if such it may be called) beyond that implied in the gratuitous use of the epithet 'purposeless' in the passage cited, and to which we shall return.

In the Rhesus monkey the female appears to be more vividly coloured than the male; therefore Mr. Darwin infers (grounding

his inference on alleged phenomena in birds) that sexual selection is reversed, and that in this case the male selects. This hypothetical reversion of a hypothetical process to meet an exceptional case will appear to many rash indeed, when they reflect that as to teeth, whiskers, general size, and superciliary ridges this monkey follows the common rule of the male excelling the female' (vol. ii. p. 294).

6

To turn now to the class on which Mr. Darwin especially relies, we shall find that even Birds supply us with numerous instances which conflict with his hypothesis. Thus, speaking of the battling of male waders, our author tells us :-'Two were seen to be thus engaged for half an hour, until one got hold of the head of the other, which would have been killed had not the observer interfered; the female all the time looking on as a quiet spectator' (vol. ii. p. 41). As these battles must take place generally in the absence of spectators, their doubtless frequently fatal termination must limit greatly the power of selection Mr. Darwin attributes to the females. The same limit is certainly imposed in the majority of Gallinaceous birds, the cocks of which fight violently; and there can be little doubt but that, as an almost invariable rule, the victorious birds mate with the comparatively passive hens.

Again, how can we explain, on Mr. Darwin's hypothesis, the existence of distinguishing male sexual marks, where it is the male and not the female bird which selects? Yet the wild turkey-cock, a distinguished bird enough, is said by Mr. Darwin (vol. ii. p. 207) to be courted by the females; and he quotes (vol. ii. p. 120) Sir R. Heron as saying, 'that with peafowl, the first advances are always made by the female.' And of the capercailzie he says, 'the females flit round the male while he is parading, and solicit his attention.'

But though, of course, the sexual instinct always seeks its gratification, does the female ever select a particular plumage? The strongest instance given by Mr. Darwin is as follows:

'Sir R. Heron during many years kept an account of the habits of the peafowl, which he bred in large numbers. He states that the hens have frequently great preference for a particular peacock. They were all so fond of an old pied cock, that one year, when he was confined though still in view, they were constantly assembled close to the trellice-walls of his prison, and would not suffer a japanned peacock to touch them. On his being let out in the autumn, the oldest of the hens instantly courted him, and was successful in her courtship. The next year he was shut up in a stable, and then the hens all courted his rival. This rival was a japanned or black-winged peacock, which to our eyes is a more beautiful bird than the common kind.'-vol. ii. p. 119.

Now

Now no one disputes as to birds showing preferences one for another, but it is quite a gratuitous suggestion that the pied plumage of the venerable paterfamilias was the charm which attracted the opposite sex; and even if such were the case, it would seem (from Mr. Darwin's concluding remark) to prove either that the peahen's taste is so different from ours, that the peacock's plumage could never have been developed by it, or (if the taste of these peahens was different from that of most peahens) that such is the instability of a vicious feminine caprice, that no constancy of coloration could be produced by its selective action.

Mr. Darwin bases his theory of sexual selection greatly on the fact that the male birds display the beauty of their plumage with elaborate parade and many curious and uncouth gestures. But this display is not exclusively used in attracting and stimulating the hens. Thus he admits that the males will sometimes display their ornaments when not in the presence of the females, as occasionally occurs with the grouse at their balz-places, and as may be noticed with the peacock; this latter bird, however, evidently wishes for a spectator of some kind, and will show off his finery, as I have often seen, before poultry or even pigs' (vol. ii. p. 86). Again, as to the brilliant Rupicola crocea, Sir R. Schomburgk says: A male was capering to the apparent delight of several others' (vol. ii. p. 87).

From the fact of 'display' Mr. Darwin concludes that 'it is obviously probable that the females appreciate the beauty of their suitors (vol. ii. p. 111). Our Author, however, only ventures to call it 'probable,' and he significantly adds: It is, however, difficult to obtain direct evidence of their capacity to appreciate beauty.' And again he says of the hen bird: It is not probable that she consciously deliberates; but she is most excited or attracted by the most beautiful, or melodious, or gallant males (vol. ii. p. 123). No doubt the plumage, song, &c., all play their parts in aiding the various processes of life; but to stimulate the sexual instinct, even supposing this to be the object, is one thing -to supply the occasion for the exercise of a power of choice is quite another. Certainly we cannot admit what Mr. Darwin affirms (vol. ii. p. 124), that an 'even occasional preference by the female of the more attractive males would almost certainly lead to their modification.'

A singular instance is given by Mr. Darwin (vol. ii. p. 111) in support of his view, on the authority of Mr. J. Weir. It is that of a bullfinch which constantly attacked a reed-bunting, newly put into the aviary; and this attack is attributed to a sort of jealousy on the part of the blackheaded bullfinch of the black

head

head of the bunting. But the bullfinch could hardly be aware of the colour of the top of its own head!

Mr. Wallace accounts for the brilliant colours of cater

a

pillars and many birds in another way. The caterpillars which are distasteful must have gained if some outward sign indicated to their would-be destroyer that its prey was disgusting morsel.' As to birds, he believes that brilliance of plumage is developed where not hurtful, and that the generally more sober plumage of the hens has been produced by natural selection, killing off the more brilliant ones exposed during incubation to trying conditions.

Now as Mr. Wallace disposes of Mr. Darwin's views by his objections, so Mr. Darwin's remarks tend to refute Mr. Wallace's positions, and the result seems to point to the existence of some unknown innate and internal law which determines at the same time both coloration and its transmission to either or to both sexes. At the same time these authors, indeed, show the harmony of natural laws and processes one with another, and their mutual interaction and aid.

It cannot be pretended that there is any evidence for sexual selection except in the class of Birds. Certain of the phenomena which Mr. Darwin generally attributes to such selection must be due, in some other classes, to other causes, and there is no proof that sexual selection acts, even amongst birds.

But in other classes, as we have seen, sexual characters are as marked as they are in the feathered group. Mr. Darwin, indeed, argues that birds select, and assumes that their sexual characters have been produced by such sexual selection, and that, therefore, the sexual characters of beasts have been similarly evolved. But we may turn the argument round and say that sexual characters not less strongly marked exist in many beasts, reptiles, and insects, which characters cannot be due to sexual selection; that it is, therefore, probable the sexual characters of birds are not due to sexual selection either, but that some unknown internal cause has equally operated in each case. The matter, indeed, stands thus: Of animals possessing sexual characters there are some in

which sexual selection cannot have acted; others in which it may possibly have acted; others again in which, according to Mr. Darwin, it has certainly acted. It is a somewhat singular conclusion to deduce from this that sexual selection is the one universal cause of sexual characters, when similar effects to those which it is supposed to cause take place in its absence.

But, indeed, what are the data on which Mr. Darwin relies as regards birds? As before said, they are 'display' by the males,