COURTSHIP AND SEX 225 



will germinate in female soil, which will not germinate in 

 male soil, though it will remain latent there. 



For the sake of clearness, let us take the same occurrence 

 on the male side. In a germ-cell (whether ovum or sper- 

 matozoon or fertilised ovum) predisposed to develop into a 

 sperm-producer, a variation arises, say, in the direction of 

 brilliant pigmentation of the skin. If it is consistent with 

 the rest of the organisation, it is realised in development ; 

 it is a success ; all the spermatozoa have it, and it is trans- 

 ferred to a multitude of ova. But it develops only in those 

 fertilised ova which are going to develop into males. It 

 does so develop because it was, to begin with, a variation — a 

 new departure — made by a male-producing gamete. It is a 

 seed which can germinate only in a male soil, which will 

 remain latent in a female soil. Thus a germinal variation 

 in the parthenogenetic ova of the bee which develop into 

 drones, will be unexpressed in the queens, but none the less 

 faithfully handed on by them. 



In the case of birds, the spur of a cock, the lingual-pouch 

 of a bustard, the two orange-coloured sacs on the neck of the 

 prairie-cock of North America, the extraordinary rugged 

 excrescence on the radius and carpo-metacarpus of the 

 extinct Dodo, the large resonating bulb associated with the 

 song-box in some drakes {e.g. the Eider) may be mentioned 

 as good examples of masculine peculiarities which develop 

 only in masculine " soil." These characters are in a some- 

 what different category from those where the dimorphism is 

 quantitative, e.g. longer feathers. By " soil," let us repeat, 

 we mean the constitutional metabolism, including the 

 secretion of the ductless glands. 



We venture then to suggest the hypothesis, that distinc- 

 tively masculine characters all arose from variations in 

 gametes predisposed or predetermined to develop into males, 

 that distinctively feminine characters all arose from variations 

 in gametes predisposed or predetermined to develop into 

 females, and that this primal difference in origin explains 

 (i) why the new gains are often confined in their expression 

 to one sex, and (2) why they hang together in a hereditary 



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