human beings. We find among birds, for instance, the most marked evidence of preference for certain individuals of the opposite sex. Pigeons afford an excellent opportunity for observation of this sentiment, for they are singularly faithful to their loves. Yet, faithful as they are in that respect, the existence of preference among them is at times additionally exhibited in the case of what is known among fanciers as a coaxer," or "gay bird," a sort of rake of a pigeon, which is sometimes able to seduce another bird from its allegiance to its mate.

Birds in their wild state can be and are watched from places of concealment by naturalists, and their whole love-making can be and often is recorded. The commonest observation shows how productive courtship and rivalry are of music among songsters. It seems idle to argue that the birds must be pleased with song. If they were not, they would not sing. It seems self-evident, and observation confirms the view, that songsters must be pleased with song, both singers and listeners. The singer, when caged and entirely by himself, often prolongs indefinitely what seems to human ears a joyous melody. Why, then, is it not certain that to his ears it must be a pleasure, and, if so, to one of the opposite sex that he may wish to mate? In the wilds he seems to sing not only to excel a rival, but to please his female choice. All three must be critical in musical performance, else there could be no rivalry through competition, and no love elicited through the most unwavering song. That the suitor and rival, or rivals, should make so much exertion as singing involves, without any object to be obtained, is incredible.

The meeting-places of birds are, naturally, as various as their habits. Among songsters, the grove is vocal with their melody, and they fly from spray to spray in delighted vagaries of wooing. Among certain birds of another kind, which may be generalized under the designation of game-birds, and which resort to the ground for locomotion more than to the air, many

species are notable for beautiful plumage and dangerous weapons. Now, it is to be remarked that, as, with rare exceptions, a bird, however game, is not called upon to use its weapons against other species, the swoop of a hawk or other enemy giving it the opportunity of using them only in the rare case where the attacker has become entangled with another quarry, it is evident that the purpose of the weapons of the male is for service against individuals of his own species, and, moreover, that these individuals are always males.

When, then, birds of these species gather together in the open spaces where they love to congregate for the holding of their love-feasts, and, by cries, struttings, and antics of all sorts, display themselves before the assembled females, "peacocking it," as the French could say by the word pavoner; when sanguinary combats, injury, and sometimes death ensue therefrom, it is not to be denied, when we find that it is only the females which can excite to such manifestations, that the females are, in their passive way, parties to and in equal degree responsible for the consequences. If the ordinary prize-fight were concerned, they would all be liable to arrest as aiders and abettors of the fight. The motives which prompt these contests are therefore just those which every human heart recognizes as perfectly comprehensible. They are fundamentally human as to inspiration, having the closest relation to conflicting choice and mating. The allurements are personal ornament and a sort of swashbuckler gallantry. That color is both liked and disliked by animals the simplest experiments prove. We have ourselves been unpleas antly near a bull's demonstration on a red flag, and we imagine that there are few who do not know that the ordinary frog seems to love a red rag as much as the bull seems to hate it.

Some of the lower animals, then, through displaying their charms to the best advantage, evidently compete with each other for the affection of individuals of their kind of the opposite sex.

This indicates, not only on the part of the males, but also on that of the females, the perception of relative desirability in individuals, both male and female. Relative admiration, of course, implies relative desirability. If there were no relative admiration there could be no relative desirability perceived, and then there would be no fighting. Not even birds fight for what they do not desire. And, throughout the scenes which have been described, perception of relative beauty, or, at least, belief in it, based on generally agreeable attributes, is the fundamental cause of the contention. If, then, beauty and gallant ways and knightly strength and skill are recognized by these animals, and recognized in the manner and with the immediate results described, that is only to say that they are proved to be rational (if our own human ways are rational) bases for choice and mating. Relative admiration, in all its phases, is clearly implied by action exactly like what should be comprehensible to higher beings possessing similar, if more exalted, sentiment. The personality of the suitor is presented, according to his knowledge, in the most favorable light for his acceptance, and that he is relatively acceptable upon the grounds upon which he counted on being pleasing is proved by the event. So, whether a bird sings, or does not sing, or is a thing of beauty and a fierce fighter, it is pleased in the same way, if not in the same degree or with the same nice discrimination, as human beings are with form, color, music, and gallantry in fight and wooing.

It is from this source that the effects of sexual selection flow. The action of certain birds in wooing was chosen as the best means of demonstrating that in nature gradual change must flow from it, because birds, of all the lower creatures, afford the greatest facilities for observation of sexual habit, are those which have consequently been the most closely observed, and at the same time are those which are the most highly gifted in the directions that render changes in them readily comprehensible.

But, wherever among animals individual preference is exercised in the relations of the sexes, similar consequences to those which we are now about to examine must ensue.

Birds are attracted not only by the beauty of color, but by the ruffling of feathers, strutting, dancing, and antics of the male, as any one can testify who has ever observed them in the state of nature. Remembering that among birds it is the female which, however much the male expresses preference, generally exercises final choice, guided by certain physical traits, such as swelling display of form and color, and by admiration of superiority in the moral traits of courage and prowess, that it is the female which makes final decision in favor of an individual male, it follows inevitably from the coincident fact that these males which are favored being those which are generally the most adorned and the best armed (else they could not be beyond others successful), must leave the greatest number of offspring of their sex as the best appointed descendants of the species. The general tendency, therefore, is for the males of certain species of birds to become more and more beautiful, and better and better armed, and so the weapons and the plumage of a species become indefinitely improved and beautified.

The gay colors and gallant ways of the barn-yard cock have attraction for the hen, as any one may observe if he will but look. Domestication does not cause either of them to lose the impulses derived from nature. In the barn-yard it is observable that the young cock comes sneaking around to gain possession, and sometimes does gain possession, of a hen, to be relinquished hastily with an affrighted squawk as the cock of the walk appears, and the other takes to flight. So also in the state of nature we may observe, among the gallinaceous fowls, the fierce old cocks battling in the arena for possession of a greater or lesser number of the attendant hens, while some young cocks, unable to try conclusions with the others, happen to please hens and elope in

a barn-yard, or indeed, human fashion, leaving the old fellows to fight it out for some of the prizes that have gone. This is one way in which the female exercises choice. In another she has Hobson's choice, none at all, and becomes the captive of the spear and bow of some supremely redoubtable master. In another, however, in a far greater degree than the first, she exercises choice among the victors. It is evident that choice she has, and choice she exercises; whereas, in the gallinaceous tribe, what the cock chiefly battles for is no choice at all, but the possession of as many hens as possible.

There are a few instances of the converse case, confirming the statement made as to the effect of the exercise of final choice. There are a few species of birds where the female, and not the male, is the active party to the courtship, and the effect just described is then reversed. It is then the female, and not the male, which is distinctively armed and adorned, and which does the fighting and directs the family. Whether or not this is a normal condition, resulting from the fact that the species is deficient in number of males, is not known. The fact, however, whatever the cause of it, serves equally well to illustrate the concomitant effect of a reversal of the ordinary course of nature, that is, the sex of the party to the nuptial contract, represented by the individual chosen for exceptional attributes, is that sex through which comes to the progeny of the same sex development of its characteristics. When the cock is the defender of the family he wears the weapons and the uniform of war. When the rôles are reversed it is the hen which wears the insignia of rank. The same thing is observable among the women who are called strong-minded.

It will at this point doubtless be inquired by some reader not conversant with the working of the laws of heredity, how it happens that to the progeny should not eventually be transmitted equally, as between the two sexes, the attributes which