No. 3.1 SEXUAL SELECTION IN SPIDERS. 149 



liveliness which all breeders of animals believe to be the most 

 attractive characteristic a male can possess." If liveliness, per 

 se, is tlie most important factor, what has produced the differ- 

 ences that exist in the modes of display in the two varieties? 

 The black fopm raises the first legs high in the air ; the 

 red form, while frequently taking the same position, has another 

 attitude peculiar to itself, in which the body is dropped to the 

 ground and the first and second pairs of legs are lowered and so 

 placed that the tips touch in front. Mere overflow of energy 

 might as well be let oS" by way of the movements of the black 

 form as by those of the red. Niger certainly gains an advant- 

 age from his superior liveliness and persistence in chasing the 

 female, but why does he never attempt to mate with her until 

 he has spent some time in posturing before her? And what is 

 the meaning of the three tufts of hair which stand erect on his 

 head ? According to Mr. Wallace's theory they should spring 

 from the leg muscles. Certainly in no part of the body is there 

 less muscular activity than at their point of origin. All these 

 minute details are insignificant when looked at alone, but taken 

 along with all the other facts, they seem to us to completely refute 

 the supposition that all the different movements — so generally 

 related to the ornamentation of the several parts — are mean- 

 ingless, and due to an excess of vitality. 



The final criticism offered by Mr. Wallace is, that suppos- 

 ing female selection to be a fact, the action of natural selection 

 would render it entirely ineffective since there would be no 

 chance that the ornamental variation would appear in just 

 those individuals which were the fittest to survive from their 

 perfect adaptation to the conditions of life, and that this 

 ineflSciency would be most complete in insects where immense 

 numbers perish in the egg, larva and pupa stages. This point 

 has been so forcibly and conclusively answered by Mr. Poulton 

 that we cannot do better than to quote his argument on the 

 subject. He says :* "Every one will admit that such a process 

 as this has been vigorously checked by the far more important 

 process of natural selection. But it does not therefore follow, as 



*The Colors of Animals, p. 307. 



