CHAFFINCH. 
303 
appear at the seasons of migration to separate into 
flocks, composed almost entirely of only one sex. 
Thus we know, that the males of many of our 
summer birds of passage arrive before the females, 
and it has been thought by some of our ornitholo- 
gists, that we receive an addition to the numbers 
of the Chaffinch in the end of autumn. About 
this period they begin to assemble in flocks, and it 
has been also thought that these flocks were, in 
many instances, composed of females alone. 
This is perhaps occasionally the case to a con- 
siderable extent, but from many young males 
having not received their full plumage, it has 
been overrated. In the south of Scotland, at 
least, the flocks are not of this exclusive sexual 
character, though in many we have noticed since 
we were aware of the opinions of others, two-thirds, 
at least, were females, while not a half of the re- 
maining third were males in full, or nearly perfect 
plumage. When kept in confinement, and regu- 
larly attended, the Chaffinch soon becomes familiar 
and even playful, but as the song has never been 
esteemed, it is not often subjected to captivity. 
In its nidification the Chaffinch ranks high as an 
architect : the nest is not often placed far from 
the ground, and when built in the cleft of some 
middle-sized tree or bush, often requires a sharp 
and penetrating eye for its detection. It is formed 
with extreme care, and is often of very beautiful 
structure, being built into the cleft or small 
branches, and the outside so carefully patched 
over with the same lichens that clothe the tree, 
