90 SEXUAL SELECTION: BIRDS. [Part IL 



bright colors to the males of any species, it has also very 

 often given a strong tendency to pugnacity. We shall 

 meet with nearly analogous cases when we treat of mam- 

 mals. On the other hand, with birds the power of song 

 and brilliant colors have rarely been both acquired by the 

 males of the aame species ; but in this case, the advantage 

 gained would have been identically the same, namely, suc- 

 cess in charming the female. Nevertheless, it must be 

 owned that the males of several brilliantly-colored birds 

 have had their feathers specially modified for the sake of 

 producing instrumental music, though the beauty of this 

 cannot be compared, at least according to our taste, with 

 that of the vocal music of many songsters. 



We will now turn to male birds which are not orna- 

 mented in any very high degree, but which nevertheless 

 display, during their courtship, whatever attractions they 

 may possess. These cases are in some respects more 

 curious than the foregoing, and have been but little no- 

 ticed. I owe the following facts, selected from a large 

 body of valuable notes, sent to me by Mr. Jenner Weir, 

 who has long kept birds of many kinds, including all the 

 British Fringillidse and Emberizidae. The bullfinch makes 

 his advances in front of the female, and then puffs out his 

 breast, so that many more of the crimson feathers are seen 

 at once than otherwise would be the case. At the same 

 time he twists and bows his black tail from side to side in 

 a ludicrous manner. The male chaffinch, also stands in 

 front of the female, thus showing his red breast, and 

 " blue-bell," as the fanciers call his head ; the wings at the 

 same time being slightly expanded, with the pure white 

 bands on the shoulders thus rendered conspicuous. The 

 .common linnet distends his rosy breast, slightly expands 

 his brown wings and tail, so as to make the best of them 

 by exhibiting their white edgings. We must, however, 

 be cautious in concluding that the wings are spread out 



