ticular individuals of opposite sexes show a decided preference for each other. Finally, Mr. Cupples, after attending to this subject for another year, has written to me, “I have had full confirmation of my former statement, that dogs in breeding form decided preferences for each other, being often influenced by size, bright color, and individual characters, as well as by the degree of their previous familiarity." In regard to horses, Mr. Blenkiron, the greatest breeder of racehorses in the world, informs me 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. The famous Monarque, for instance, would never consciously look at the dam of Gladiateur, and a trick had to be practiced. We can partly see the reason why valuable racehorse stallions, which are in such demand as to be exhausted, should be so particular in their choice. Mr. Blenkiron has never known a mare reject a horse; but this has occurred in Mr. Wright's stable, so that the mare had to be cheated. Prosper Lucas“ quotes various statements from French authorities, and remarks, "On voit des étalons qui s'éprennent d'une jument, et négligent toutes les autres." He gives, on the authority of Baëlen, similar facts in regard to bulls; and Mr. H. Reeks assures me that a famous short-horn bull belonging to his father "invariably refused to be matched with a black cow." Hoffberg, in describing the domesticated reindeer of Lapland, says, "Fœminæ majores et fortiores mares præ cæteris admittunt, ad eos confugiunt, a junioribus agitatæ, qui hos in fugam conjiciunt. A clergyman who has bred many pigs asserts that sows often reject one boar and immediately accept another. 97 49 From these facts there can be no doubt that, with most of our domesticated quadrupeds, strong individual antipathies 48 "Traité de l'Héréd. Nat." tom. ii., 1850, p. 296. and preferences are frequently exhibited, and much more commonly by the female than by the male. This being the case, it is improbable that the unions of quadrupeds in a state of nature should be left to mere chance. It is much more probable that the females are allured or excited by particular males, who possess certain characters in a higher degree than other males; but what these characters are we can seldom or never discover with certainty. CHAPTER XVIII SECONDARY SEXUAL CHARACTERS OF MAMMALS-continued Voice-Remarkable sexual peculiarities in seals-Odor-Development of the hair-Color of the hair and skin-Anomalous case of the female being more ornamented than the male-Color and ornaments due to sexual selection-Color acquired for the sake of protection-Color, though common to both sexes, often due to sexual selection-On the disappearance of spots and stripes in adult quadrupeds—On the colors and ornaments of the Quadrumana-Summary Q UADRUPEDS use their voices for various purposes, as a signal of danger, as a call from one member of a troop to another, or from the mother to her lost offspring, or from the latter for protection to their mother; but such uses need not here be considered. We are concerned only with the difference between the voices of the sexes, for instance between that of the lion and lioness, or of the bull and cow. Almost all male animals use their voices much more during the rutting season than at any other time; and some, as the giraffe and porcupine,' are said to be completely mute excepting at this season. As the throats (i.e., the larynx and thyroid bodies') of stags periodically become enlarged at the beginning of the breeding season, it might be thought that their powerful voices must be somehow of high importance to them; but this is very doubtful. From information given to me by two experienced observers, Mr. McNeill and Sir P. Egerton, it 1 Owen, "Anatomy of Vertebrates," vol. iii. p. 585. seems that young stags under three years old do not roar or bellow, and that the old ones begin bellowing at the commencement of the breeding season, at first only occasionally and moderately, while they restlessly wander about in search of the females. Their battles are prefaced by loud and prolonged bellowing, but during the actual conflict they are silent. Animals of all kinds which habitually use their voices utter various noises under any strong emotion, as when enraged and preparing to fight; but this may merely be the result of nervous excitement, which leads to the spasmodic contraction of almost all the muscles of the body, as when a man grinds his teeth and clinches his fists in rage or agony. No doubt stags challenge each other to mortal combat by bellowing; but those with the more powerful voices, unless at the same time the stronger, better armed, and more courageous, would not gain any advantage over their rivals. It is possible that the roaring of the lion may be of some service to him by striking terror into his adversary; for when enraged he likewise erects his mane and thus instinc. tively tries to make himself appear as terrible as possible. But it can hardly be supposed that the bellowing of the stag, even if it be of service to him in this way, can have been important enough to have led to the periodical enlargement of the throat. Some writers suggest that the bellowing serves as a call to the female; but the experienced observers above quoted inform me that female deer do not search for the male, though the males search eagerly for the females, as indeed might be expected from what we know of the habits of other male quadrupeds. The voice of the female, on the other hand, quickly brings to her one or more stags, as is well known to the hunters who in wild countries imitate her cry. If we could believe that the male had the power to excite or allure the female by his voice, the periodical See Major W. Ross King ("The Sportsman in Canada," 1866, pp. 53, 131) on the habits of the moose and wild reindeer. enlargement of his vocal organs would be intelligible on the principle of sexual selection, together with inheritance. limited to the same sex and season; but we have no evidence in favor of this view. As the case stands, the loud voice of the stag during the breeding season does not seem to be of any special service to him, either during his courtship or battles, or in any other way. But may we not believe that the frequent use of the voice, under the strong excitement of love, jealousy, and rage, continued during many generations, may at last have produced an inherited effect on the vocal organs of the stag, as well as of other male animals? This appears to me, in our present state of knowledge, the most probable view. The voice of the adult male gorilla is tremendous, and he is furnished with a laryngeal sac, as is the adult male orang. The gibbons rank among the noisiest of monkeys, and the Sumatra species (Hylobates syndactylus) is also furnished with an air-sac; but Mr. Blyth, who has had oppor. tunities for observation, does not believe that the male is noisier than the female. Hence, these latter monkeys probably use their voices as a mutual call, and this is certainly the case with some quadrupeds; for instance, the beaver. Another gibbon, the H. agilis, is remarkable from having the power of giving a complete and correct octave of musical notes, which we may reasonably suspect serves as a sexual charm; but I shall have to recur to this subject in the next chapter. The vocal organs of the American Mycetes caraya are one-third larger in the male than in the female, and are wonderfully powerful. These monkeys in warm weather make the forests resound at morning and evening with their overwhelming voices. The males begin the dreadful concert, and often continue it during many hours, the Owen, "Aratomy of Vertebrates," vol. iii. p. 600. Mr. Green, in the "Journal of the Linnæan Society," vol. x. Zoology, 1869, p. 362. C. L. Martin, "General Introduction to the Nat. Hist. of Mamm. Animals," 1841, p. 431, |