protuberances, horns, air-distended sacks, top-knots, naked shafts,
plumes and lengthened feathers gracefully springing from all parts of
the body. The beak and naked skin about the head, and the feathers, are
often gorgeously coloured. The males sometimes pay their court by
dancing, or by fantastic antics performed either on the ground or in
the air. In one instance, at least, the male emits a musky odour, which
we may suppose serves to charm or excite the female; for that excellent
observer, Mr. Ramsay (1. Ibis, vol. iii. (new series), 1867, p.
414.), says of the Australian musk-duck (Biziura lobata) that the
smell which the male emits during the summer months is confined to that
sex, and in some individuals is retained throughout the year; I have
never, even in the breeding-season, shot a female which had any smell
of musk. So powerful is this odour during the pairing-season, that it
can be detected long before the bird can be seen. (2. Gould, Handbook
of the Birds of Australia, 1865, vol. ii. p. 383.) On the whole, birds
appear to be the most aesthetic of all animals, excepting of course
man, and they have nearly the same taste for the beautiful as we have.
This is shewn by our enjoyment of the singing of birds, and by our
women, both civilised and savage, decking their heads with borrowed
plumes, and using gems which are hardly more brilliantly coloured than
the naked skin and wattles of certain birds. In man, however, when
cultivated, the sense of beauty is manifestly a far more complex
feeling, and is associated with various intellectual ideas.
Before treating of the sexual characters with which we are here more
particularly concerned, I may just allude to certain differences
between the sexes which apparently depend on differences in their
habits of life; for such cases, though common in the lower, are rare in
the higher classes. Two humming-birds belonging to the genus
Eustephanus, which inhabit the island of Juan Fernandez, were long
thought to be specifically distinct, but are now known, as Mr. Gould
informs me, to be the male and female of the same species, and they
differ slightly in the form of the beak. In another genus of
humming-birds (Grypus), the beak of the male is serrated along the
margin and hooked at the extremity, thus differing much from that of
the female. In the Neomorpha of New Zealand, there is, as we have seen,
a still wider difference in the form of the beak in relation to the
manner of feeding of the two sexes. Something of the same kind has been
observed with the goldfinch (Carduelis elegans), for I am assured by
Mr. J. Jenner Weir that the bird-catchers can distinguish the males by
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