The Descent of Man

one splendidly-coloured species, the sexes differ
so much that they were at first thought to be
specifically distinct. (22. Namely, Cyanalcyon,
Gould's 'Handbook to the Birds of Australia,'
vol. i. p. 133; see, also, pp. 130, 136.) Mr. R.B.
Sharpe, who has especially studied this group,
has shewn me some American species (Ceryle)
in which the breast of the male is belted with
black. Again, in Carcineutes, the difference
between the sexes is conspicuous: in the male
the upper surface is dull-blue banded with
black, the lower surface being partly fawncoloured,
and there is much red about the head;
in the female the upper surface is reddishbrown
banded with black, and the lower surface
white with black markings. It is an interesting
fact, as shewing how the same peculiar
style of sexual colouring often characterises
allied forms, that in three species of Dacelo the
male differs from the female only in the tail
being dull-blue banded with black, whilst that
of the female is brown with blackish bars; so