SEXUALLY LIMITED INHERIT AX GE. 
161 
C«. 
Ap. 
XV. 
a;r e P SUc h variations would be of no service until the 
titj ()li ° r re pvoduction had arrived, and there was compe- 
'vliicj ( ‘ e ^ vveen rival males. But in the case of birds 
tli e llVe the ground and which commonly need 
Vf? tecti0n dull colours, bright tints would be far 
e dan : 
to 
th 
Serous to the young and inexperienced than 
v hi (1 (t . a ^ u ^ m ales. Consequently the males which 
111 brightness whilst young would suffer much 
ti 0ft Ucti °n and be eliminated through natural selec- 
ting ’ ° u the other hand the males which varied in 
turner when nearly mature, notwithstanding that 
Vj Ve ere exposed to some additional danger, might sur- 
' v o u i c | in<l b'°m being favoured through sexual selection, 
J&aj b l ’°create their kind. The brightly-coloured young 
- ein b r destroyed and the mature ones being suc- 
of la their courtship, may account, on the principle 
.lotion existing between the period of variation 
iti ail 16 form of transmission, for the males alone of 
co] OUrs lr ds, having acquired and transmitted brilliant 
ah 6atls their male offspring alone. But I by no 
th 6 j. Wl8 n to maintain that the influence of age on 
Hie transmission is indirectly the sole cause of 
Of J Iea t difference in brilliancy between the sexes 
^ a } T birds. 
b ' Vl ^b all birds in which the sexes differ in colour, it 
bee^ Ill ^ er estiug question whether the males alone have 
Wijjg 1 °difled through sexual selection, the females 
!lt oul ° as as this agency is concerned, unchanged 
^ Partially changed ; or whether the females have 
J ,6l -ially modified through natural selection for the 
j Protection, I will discuss this question at con- 
*hp 0rt e length, even at greater length than its intrinsic 
ance deserves ; for various curious collateral points 
\'oj_ be conveniently considered. 
