United States or India ? Vote for the TOP Country of the Week !


Choice exerted by the female Length of courtship Unpaired birds Mental qualities and taste for the beautiful Preference or antipathy shewn by the female for particular males Variability of birds Variations sometimes abrupt Laws of variation Formation of ocelli Gradations of character Case of Peacock, Argus pheasant, and Urosticte.

Uraniidae, coloration of the. Urodela. Urosticte Benjamini, sexual differences in. Use and disuse of parts, effects of; influence of, on the races of man. Uterus, reversion in the; more or less divided, in the human subject; double, in the early progenitors of man. Vaccination, influence of. Vancouver Island, Mr. Sproat on the savages of; natives of, eradication of facial hair by the.

Argyll, Duke of, on the physical weakness of man; the fashioning of implements peculiar to man; on the contest in man between right and wrong; on the primitive civilisation of man; on the plumage of the male Argus pheasant; on Urosticte Benjamini; on the nests of birds. Argynnis, colouring of the lower surface of. Aricoris epitus, sexual differences in the wings of.

Whilst one male was descending, the other would shoot up and come slowly down expanded. The entertainment would end in a fight between the two performers; but whether the most beautiful or the most pugnacious was the accepted suitor, I know not." Mr. Gould, after describing the peculiar plumage of the Urosticte, adds, "that ornament and variety is the sole object, I have myself but little doubt."

In the female of the Urosticte I noticed extremely minute or rudimental white tips to the two outer of the four central black tail- feathers; so that here we have an indication of change of some kind in the plumage of this species. If we grant the possibility of the central tail- feathers of the male varying in whiteness, there is nothing strange in such variations having been sexually selected.

Thus we can understand and in no other way as it seems to me the present condition and origin of the ornaments on the wing-feathers of the Argus pheasant. Mr. Gould several years ago pointed out to me a humming-bird, the Urosticte benjamini, remarkable for the curious differences between the sexes.

Nor is it strange that variations in the tail-feathers of the Urosticte should have been specially selected for the sake of ornament, for the next succeeding genus in the family takes its name of Metallura from the splendour of these feathers. We have, moreover, good evidence that humming-birds take especial pains in displaying their tail-feathers; Mr.

What makes the case more curious is that, although the colouring of the tail differs remarkably in both sexes of many kinds of humming-birds, Mr. Gould does not know a single species, besides the Urosticte, in which the male has the four central feathers tipped with white. He answers "none whatever"; and I quite agree with him. But can this be so confidently said of sexual selection?