Chap. XVI. 
SUMMAKY. 
233 
but have special means for charming the female. With 
some it is the power of song, or of emitting strange 
cries, or of producing instrumental music, and the males 
in consequence differ from the females in their vocal 
organs, or in the structure of certain feathers. From 
the curiously diversified means for producing various 
sounds we gain a high idea of the importance of this 
means of courtship. Many birds endeavour to charm 
the females by love-dances or antics, performed on the 
ground or in the air, and sometimes at prepared places. 
But ornaments of many kinds, the most brilliant tints, 
combs and wattles, beautiful plumes, elongated feathers, 
top-knots, and so forth, are by far the commonest 
means. In some cases mere novelty appears to have 
acted as a charm. The ornaments of the males must 
be highly important to them, for they have been ac- 
quired in not a few cases at the cost of increased danger 
from enemies, and even at some loss of power in fight-- 
ing with their rivals. The males of very many spe- 
cies do not assume their ornamental dress until they 
arrive at maturity, or they assume it only during the 
breeding-season, or the tints then become more vivid. 
Certain ornamental appendages become enlarged, turgid, 
and brightly-coloured during the very act of courtship. 
The males display their charms with elaborate care and 
to the best effect ; and this is done in the presence of 
the females. The courtship is sometimes a prolonged 
affair, and many males and females congregate at an 
appointed place. To suppose that the females do not 
appreciate the beauty of the males is to admit that 
their splendid decorations, all their pomp and display, 
are useless ; and this is incredible. Birds have fine 
powers of discrimination, and in some few instances it 
can be shewn that they have a taste for the beautiful. 
The females, moreover, are known occasionally to 
