244 INSTINCT. Chap. VII. 



cuckoo ejecting its foster-brothers, — ants making slaves, 

 — the larvae of ichneumonidae feeding within the live 

 bodies of caterpillars, — not as specially endowed or 

 created instincts, but as small consequences of one 

 general law, leading to the advancement of all organic 

 beings, namely, multiply, vary, let the strongest live 

 and the weakest die. 



