212 DEGENERATION sec. 



tion, on the other, the cessation of the stimulation caused by 

 the action of insects in gathering the pollen. 



Moreover, correlation plays a particularly important part 

 in the sexual organs, at least in the animal kingdom, and it 

 is well known how prone stamens are to degenerate in plants 

 generally. 



Weismann lays particular stress on the fact that wiugless- 

 ness as a character of the asexual workers among ants is 

 inherited from the winged sexual individuals. " It is there- 

 fore impossible that the degeneration of the wings, possibly 

 caused by disuse in the individual animal, should be trans- 

 mitted to a succeeding generation." 



The immediately obvious reply to this is mentioned by 

 Weismann himself, when he says : " It might perhaps be 

 maintained that the loss of the wings occurred previously to 

 that of the power of reproduction, but such a suj)position 

 must on very definite grounds, which I must here omit to 

 particularise, be rejected." But what if the degeneration of 

 the wings and of the sexual organs proceeded simultaneously — 

 correlatively ? This appears to me probable, on account of 

 the important correlative connections of the sexual organs. I 

 shall subsequently have to speak further, in reference to bees, 

 of the power of correlation, which shows itself especially 

 in the modification of the sexual organs. What is there 

 said will apply to the case of ants, which is not completely 

 disposed of here. 



The absence of hair in the larger marine mammals is 

 attributed to the cessation of natural selection : " The hairy 

 covering is no longer necessary in the water — the layer of fat 

 supplies its place." Here again I cannot banish the idea 

 that physiological causes are also concerned in this alteration. 

 It is certainly striking that no animal which develops and 

 always lives in the open water possesses a horny epidermis, 

 and hairs are horny structures of the epidermis. Whales, to 



