SELECTION 157 



ever and wherever opportunity offers, at the 

 improvement of each organic being in relation 

 to its animate and inanimate conditions of 

 life. It may operate on characters which 

 we are apt to consider of very trifling im- 

 portance, and its . a^immi1a.|.]ftn of grnall 

 t np. ^flpxpected correlative 



It jnay affect the egg, the seed, or 

 the young as easily as the adult; iyaa^Hul^gt 

 the structure of young t.q pfl.rpnt. and of 

 parent to young; and in social animals it may 

 ' nf pagh for the benefit 



of^all. In the later editions of the "Origin" 

 a brief account of sexual selection is given 

 at this point. 



The theory of natural selection is then 

 illustrated by particular instances. Thus 

 Dflfwip pictures the formation of swift 

 varieties of wolves, much in the same way 

 as greyhounds have been evolved by man. 

 Or, again, ha^ refers to the g frrf tl>r m -^f 

 Tvp.ftfrPI by flowers, its use to insects, the 

 action of these in carrying the fertilizing 

 pollen, its advantage in intercrossing, and the 

 resiiltantjinely 



and inseqt to each, other through th^ 



* g p^ r *ti 



variations. 



Qircjiiastances favourable for the pro- 

 duction of new forms through jiaturai selec- 



