6 
POPULAR HISTORY OP BIRDS. 
colours^ as if Providence meant to favour their personal con- 
cealment^ and conseqaently that of their nest and young, 
from the depredations of birds of prey; while among the 
latter,, such as eagles, owls, hawks, etc., which are under no 
such apprehension, the females are uniformly covered with 
richer-coloured plumage than the males "^/^ 
Among exotic birds the toucans are a notable exception 
to this rule; among British birds may be specified the 
goldfinch, the female of which is scarcely less bright than 
the male. The first plumage of the males of gaily-coloured 
birds is generally of the same sober hue as the female ; in 
the toucans the young birds are nearly as gay in colour as 
their parents. 
The males of many birds, especially of the order Passeres, 
are possessed of the power of song, which, in many cases, 
certainly serves to enliven the female when on the nest. 
This however does not seem to be its only use, as the 
males of many birds sing also at times of the year when 
their partners are not engaged in the task of incubation. 
On this subject we may quote the words of Mr. Water- 
ton t: — " I sometimes peevishly ask myself, why should na- 
* Amer. Ornith. vol. ii. p. 233. 
t Essays on Natural History, p. 252. 
