Male humming-birds (Figs. 48 and 49) almost vie with birds of paradise
in their beauty, as every one will admit who has seen Mr. Gould s
splendid volumes, or his rich collection. It is very remarkable in how
many different ways these birds are ornamented. Almost every part of
their plumage has been taken advantage of, and modified; and the
modifications have been carried, as Mr. Gould shewed me, to a wonderful
extreme in some species belonging to nearly every sub-group. Such cases
are curiously like those which we see in our fancy breeds, reared by
man for the sake of ornament; certain individuals originally varied in
one character, and other individuals of the same species in other
characters; and these have been seized on by man and much augmented as
shewn by the tail of the fantail-pigeon, the hood of the jacobin, the
beak and wattle of the carrier, and so forth. The sole difference
between these cases is that in the one, the result is due to man s
selection, whilst in the other, as with humming-birds, birds of
paradise, etc., it is due to the selection by the females of the more
beautiful males.
I will mention only one other bird, remarkable from the extreme
contrast in colour between the sexes, namely the famous bell-bird
(Chasmorhynchus niveus) of S. America, the note of which can be
distinguished at the distance of nearly three miles, and astonishes
every one when first hearing it. The male is pure white, whilst the
female is dusky-green; and white is a very rare colour in terrestrial
species of moderate size and inoffensive habits. The male, also, as
described by Waterton, has a spiral tube, nearly three inches in
length, which rises from the base of the beak. It is jet-black, dotted
over with minute downy feathers. This tube can be inflated with air,
through a communication with the palate; and when not inflated hangs
down on one side. The genus consists of four species, the males of
which are very distinct, whilst the females, as described by Mr.
Sclater in a very interesting paper, closely resemble each other, thus
offering an excellent instance of the common rule that within the same
group the males differ much more from each other than do the females.
In a second species (C. nudicollis) the male is likewise snow-white,
with the exception of a large space of naked skin on the throat and
round the eyes, which during the breeding-season is of a fine green
colour. In a third species (C. tricarunculatus) the head and neck alone
of the male are white, the rest of the body being chestnut-brown, and
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