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Show 246 SEXUAL SELECTION: MAMMALS. PART Jf. is therefore probable that their presence or absence in the females of some species, and their more or loss perfect condition in the females of other species, depend, not on their being of some special use, but simply on the form of inheritance whieh has prevailed. It accords with this view that eren in the same restricted genus both sexes of some species, and the males alon(• of other species, are thus provided. It is a remarkable fact that, although the females of Antilope bezoartica are normally destitute of horns, Mr. Blyth has seen 110 less than three females thus furnished; and there was no reason to suppose that they were old or diseased. The males of this species have long straight spirated horns, nearly parallel to each other, and directed backwards. Those of the female, when present, are very different in shape, for they are not spirated, and spreading widely bend round, so that theit· points are direeted forwards. It is a still more remarkable fact that in the castrated male, as :Mr. Blyth informs me, the horns are of the same peculiar shape as in the female, but longer and thicker. In all cases the differenceR betweou the horns of the males and females, and of castrated and entire males, probably depend on various causes,-on the more or less complete transference of male characters to the females,-on the former state of the progenitors of the species,-and partly perhaps 011 the horns being differently nourished, in nearly the same manner as the spurs of the domestic cock, when inserted into the comb or other parts of the body, assume varions abnormal forms from being differently nourished. In all the wild species of goats and sheep the horus are larger in the male than in the female, aucl are sometimes quite absent in the latter.12 In several domestic 12 Grny, ' Calaloguo M:nmm. Brit. 1\ius.' part iii. 1852, p. lGO. CHAP. XVII. LA.W OF DA.TTLE. 247 breeds of the sheep and goat, the males alone are furnished with horns; and it is a significant fact, that in one such breed of sheep on the Guinea coast, tho horns are not developed, as Mr. Winwood Heade informs me, in the castrated male; so that they are affected in this respect like the horns of stags. In some breells, as in that of N. Wales, in which both sexes are properly horned, the ewes are very liable to be hornless. In these same sheep, as I have been informed by a trustworthy witness who purposely inspected a flock durinothe lambing-season, the horns at birth are generall; more fully developed in the male than in the female. With the adult musk-ox ( Ovibos moschatus) the horns of the male are larger than those of the female, and in the latter the bases do not touch.13 In regard to ordinary cattle Mr. Blyth remarks : "In most of the wild bovine " animals the horns are both longer and thicker in the " bull than in the cow, and in the cow-banteng (Bos "sondaicus) the horns are remarkably small, and in" clined much backwards. In the domestic races of "cattle, both of tho humped and humpless types, the " horns are sho~'t and thick in the Lull, longer and '' more slender m the cow and ox ; and in the Indian ':buffalo, they are shorter and thicker in the bull, longer " and more slender in the cow. In the wild gaour '·(B. gaurus) the horns are mostly both longer and " thicker in the bull than in the cow." 14 Hence with most sheath-horned ruminants the horns of the male are either longer or stronger than those of the female. With the Rhinoceros simus, as I may here add, the horns of the female are generally longer but less powerful than in the male ; and in some other sper.ies of 13 Richardson, 'Fauna Bor. Americana,' p. 278. u • Lal)d aud Water,' 18G7, p. 346. |
