It is useless, however, to rehearse the opinions of the various writers who have dealt with this subject. It is perhaps sufficient to state that the great beauty of males has usually been accepted as evidence of their superiority over the females. In his chapter, “The Male generally more Modified than the Female,” Mr. Darwin remarks: “Appearances would indicate that not the male which is most attractive to the female is chosen, but the one which is least distasteful.” He says that the aversion of female birds for certain males renders the season of courtship one of great anxiety and discomfiture, not only to many of the more poorly endowed aspirants, but to those also which are more magnificently attired—that the pairing ground becomes a field of battle, upon which, while parading their charms to the best advantage, is sacrificed much of the gorgeous plumage of the contestants. On the wooing ground are displayed for the admiration and approval of the females, all the physical attractions of the males, as well as the mental characters correlated with them, namely, courage, and pugnacity or perseverance. According to Mr. Darwin, with the exception of vanity, no other quality is in any considerable degree manifested by male birds, but to such an extent has love of display been developed in many of them, notably the pea-fowl, that, “in the absence of females of his own species, he will show off his finery before poultry and even pigs.” We are assured that the higher we ascend in the animal kingdom the more frequent and more violent become two desires in the male: “the desire of appearing beautiful, and that of driving away rivals.” According to Mr. Darwin’s theory of development, because of the indifference of the female among the lower orders of life to the processes of courtship, it has been necessary for the male to expend much energy or vital force in searching for her—in contending with his rivals for possession of her person, and in performing various acts to please her and secure her favours. While excessive eagerness in courtship is the one all-absorbing character of male fishes, birds, and mammals, we are assured that with the females, pairing is not only a matter of indifference, but that courtship is actually distasteful to them, and, therefore, that the former must resort to the various means referred to in order to induce the latter to submit to their advances.