776 THE DESCENT OF MAN 



toe same race; for this indicates reversion — long lost char- 

 acters being very apt to vary on reappearance. 



Nor mast we overlook the part which sexual selectioa 

 may have played in later times; for we know that, with 

 savages, the men of the beardless races take infinite pains 

 in eradicating every hair from their faces as something 

 odious, while the men of the bearded races feel the great- 

 est pride in their beards. The women, no doubt, partici- 

 pate in these feelings, and, if so, sexual selection can hardly 

 have failed to have effected something in the course of later 

 times. It is also possible that the long-continued habit of 

 eradicating the hair may have produced an inherited effect. 

 Dr. Brown-Sdquard has shown that if certain animals are 

 operated on in a particular manner, their offspring are af- 

 fected. Further evidence could be given of the inheritance 

 of the effects of mutilations; but a fact lately ascertained 

 by Mr. Salvin" has a more direct bearing on the present 

 question; for he has shown that the motmots, which are 

 known habitually to bite off the barbs of the two central 

 tail feathers, have the barbs of these feathers naturally 

 somewhat reduced." Nevertheless, with mankind, the habit 

 of eradicating the beard and the hairs on the body would 

 probably not have arisen until these had already become 

 by some means reduced. 



It is difficult to form any judgment as to how the hair 

 on the head became developed to its present great length 

 in many races. Eschricht" states that in the human foetus 

 the hair on the face during the fifth month is longer than 

 that on the head; and this indicates that our semi-human 

 progenitors were not furnished with long tresses, which 

 must therefore have been a late acquisition. This is like- 

 wise indicated by the extraordinary difference in the length 



s* "Oa the tail feathers of Momotus," "Proc. Zoolog. Soc," 18T3, p. 429. 



^ Mr. Sproat has suggested ("Scenes and Studies of Savage Life," 1868, p. 

 25) this same view. Some distinguished ethuologists, among others M. Gosse 

 of Geneva, believe that artillcial modifications of the skuU tend to be inherited. 



»8 "Ueber die Eiohtuna" ibid., s. 40. 



