204 
SEXUAL SELECTION : BIRDS. 
Part' 
share in hatching the eggs; hut the female like**? 
attends to the young . 20 I have not been able to (]li ' 
covei whether with these species the young resemble ^ 
adult males more closely than the adult females ; ^ 
the comparison is somewhat difficult to make on a ccoU" 
of the double moult. 
Turning now to the Ostrich order: the male of the co & 
mon cassowary ( Casuarius gcdecUus) would be tho«g lj * 
by any one to be the female, from his smaller size ^ 
from the appendages and naked skin about his h e " 1 
being much less brightly coloured; and I am infor^' 
by Mr. Bartlett that in the Zoological Gardens h / 
certainly the male alone who sits on the eggs and ta 1; f 
care of the young . 21 The female is said by Mr. T. ^ V ' 
Wood 22 to exhibit during the breeding-season a W 0 * 
pugnacious disposition; and her wattles then b ec° ,1)C 
enlarged and more brilliantly coloured. So again 
female of one of the emus ( Dromceus irroratus) is c ° r 
siderably larger than the male, and she possesses/ 
s ight top-knot, but is otherwise undistinguishable 1,1 
plumage. She appears, however, “to have grea t<?r 
power, when angry “or otherwise excited, of erectfr# 
“hke a turkey-cock, the feathers of her neck ^ 
Britain Prof w stoteraents ’ see Mr - Goulds ‘Birds of 
“ Pl0f - Newtou informs me that he has long been convm 1 ^ 
own observations ami from those of others, that the , e 
the above-named spedes take either the whole or a large share of/ 
^ tUat ‘key ".hew much grLer devo'j 
towards their young when in danger, than do the females,” So / 
as he informs me, with Lhmm lappmim and some few other 
in which the females are larger and have more strongly eon**** 
colours than the males. J 
ii. P’ 
vol. 
i -lo T1 i m t « f °f am f Wa]lace > ‘Mhtay Archipelago,’ von 
IdO) assert that the male and female sit alternately on the egg.’’ Z 
this assertion, as Mr. Bartlett thinks, may he accounted for W “ 
female visiting the nest to lay Jier egga. 
22 t 
The Student,’ April, 1870, p, 124 . 
