1892. 



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forcible answer than this can be made, to wit the following : Mr. 

 Wallace has been to some extent misled by the influence of language, 

 Natural Selection and Sexual Selection being unconsciously conceived 

 by him as independent powers or causes. He has forgotten that, 

 however successful an individual male may be in the struggle for 

 existence, he cannot bequeath his superior endowments and faculties 

 to offspring unless some female appreciates him sufficiently to grant 

 him the favours of sexual intercourse. Mr. Wallace a.rgues as 

 though the superior male, facile pvinceps in the competition for a 

 living, could found a line of descendants inheriting his own health 

 and vigour without female assistance, and could afford to scorn and 

 ignore the petty female standards. On the contrary, the fact is that 

 there is competition in love as well as in life. It is an observed fact 

 that males, in very many instances, fight together for the possession 

 of the females, and, in other cases, compete with one another by the 

 display of adornment or the efforts of song for the favour of the oppo- 

 site sex. It is also an observed fact, in many cases, that where this 

 sexual competition is most conspicuous there the secondary sexual 

 characters are most developed, and that competition is conducted 

 solely in respect of these characters. A male that excels in the 

 struggle for existence is a complete failure, so far as the species is 

 concerned, unless he can succeed also in finding mates. In view of 

 the fact that competition for mates occurs among those males which 

 have already survived the process of Natural Selection, and are all 

 able and eager to beget offspring, it is a certainty that those will 

 leave most offspring to succeed them who are most able, either by 

 force or charm, by weapQns or adornments, as the case may be, to 

 constitute themselves the fathers of the next generation. Without 

 going so far as Mr. Romanes, and saying that this is the argument 

 that Darwin would have used, I venture to think it is more consis- 

 tent with the Darwinian method and doctrine than that employed by 

 Mr. Romanes himself. At the same time, the formulation of the 

 argument is not intended to imply any admission that we regard the 

 actual selection of individuals as the essential and most important 

 result in sexual any more than in " natural " or general competition. 

 Subsidiary objections of Mr. Wallace's are, that there is no 

 evidence that hen birds, for instance, are charmed by the beauty or 

 voice of the males, and that, if there were, it would be necessary to 

 the theory that the taste of the females should be uniform in all 

 individuals and constant throughout many generations. Mr. Romanes' 

 reply is practically what he condemns in another place as the argu- 

 ment from ignorance. We do not know, he says, what sentiments 

 may be in the mind of a hen, and as for the constancy and uniformity, 

 we know very little about the psychology of the lower animals. Here, 

 again, I would venture to suggest a better reply. We do not require 

 to assume an aesthetic sense in the hen birds. Without going deeply 

 into psychology it is obviously probable that it is simply the sexual 

 desire which is alone concerned in Sexual Selection. This desire is 

 usually not easily excited in the female, and the function of subsidiary 

 sexual organs and their display or exertion is probably enough the 

 excitement of this desire, without which that of the male cannot be 

 gratified. And the explanation on this view of the constancy of the 

 selection in the same species is merely heredity. The sexual desire 

 of the female has a hereditary association with certain sensory stimuli, 

 and the means of furnishing these stimuli are constantly reproduced 

 and improved by inheritance in the males. I will not develop these 

 considerations further. They are, perhaps, too much beyond the 



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