“Some Longicorns, especially certain Prionidæ, offer an exception to the rule that the sexes of Beetles do not differ in colour. Most of these insects are large and splendidly coloured. The males of the genus Pyrodes ... are generally redder but rather duller than the females, the latter being coloured of a more or less splendid golden-green. On the other hand, in one species the male is golden-green, the female being tinted with red and purple. In the genus Esmeralda the sexes differ so greatly in colour that they have been ranked as distinct species: in one species both are of a beautiful shining green, but the male has a red thorax. On the whole, as far as I could judge, the females of those Prionidæ in which the sexes differ are coloured more richly than the males, and this does not accord with the common rule in regard to colour when acquired through sexual selection.” While there is nothing very remarkable in the two sexes being coloured alike, it is certainly strange to find the female more brilliantly coloured than the male. And this because among the higher vertebrates, as among the birds, the female exceeds in brilliance only where she also plays the rôle of wooer instead of wooed; leaving to the male the whole responsibility of rearing the family. With the Beetles the family has to rear itself, parental care being limited to the right disposal of the eggs. By some change in the character of the germ-plasm the females may have, in these cases, acquired more “maleness,” more of the qualities which are answerable for the secondary sexual characters of the male, or, what seems rather to be the case here, a result like that which has been reached in certain of the Pigeons and Parrots has been arrived at. That is to say, the tendency to intensification of pigment in the female struck out a new line, instead of following that of the male. This rather rare form of sexual dimorphism is also met with, it will be remembered, among the Butterflies and Moths. While brilliant colour is the more usual form of ornament among the Beetles, there are many species wherein the males have developed enormous horns, or have greatly exaggerated the length of the jaws; and these outgrowths give the impression of a formidable armature, but so far as the evidence goes this is by no means the case. They must therefore be relegated to the category of “ornaments,” though the term “excrescences” would more fittingly apply to them, for they are “ornaments” only from a human standpoint. At any rate, there is no evidence whatever that they serve to enhance their possessors in the eyes of the females.