94 
SEXUAL SELECTION : BIKDS. 
Pab 1 1 
together, but it appears that when sexual select^ 
has been highly influential, and has given bri? , 
colours to the males of any species, it has also 
often 
W 
given a strong tendency to pugnacity. j 
shall meet with nearly analogous cases when we 
of mammals. On the other band, with birds the po"'^ 
of song and brilliant colours have rarely been h\. 
t,l" f 
, 11 / 
acquired by the males of the same species ; but i» 
case, the advantage gained would have been identic^ 
the same, namely success in charming the fen 1 " j 
Nevertheless it must be owned that the males of sev" 1 ' 
brilliantly-coloured birds have had their feathers f ! j 
cially modified for the sake of producing instruxne®^ 
music, though the beauty of this cannot be compn re j 
at least according to our taste, with that of the v° L ’ 
music of many songsters. 
We will now turn to male birds which are 
nflt 
ornamented in 
any very high degree, but "'1'“ , 
nevertheless display, during their courtship, what® 
attractions they may possess. These cases are in so" 1 
respects more curious than the foregoing, and have *•> j 
but little noticed. I owe the following facts, se ^ eC q r , 
from a large body of valuable notes, sent to me by ^ 
Jenner Weir, who has long kept, birds of many kinds* 
eluding all the British Friugilikke and Emberizidffi. -* 
bullfinch makes his advances in front of the fen 1 " 
crimson feathers arc seen at once than otherwise ' v< 
and then puffs out his breast, so that many more o* - j 
9 
be the case. At the same time he twists and bows 
black tail from side to side in a ludicrous manner. 
rp|j<? 
male chaffinch also stands in front of the female, 
shewing his red breast, and “blue bell, ” as the fa»"" 
call his head ; the wings at the same time being sli- 1 k 
expanded, with the pure white bands on the shorn 1 ,, 
thus rendered conspicuous. The common linnet diste 
