Heredity in Man. 331 



reply is that obviously this is a congenital character on 

 which natural selection would take effect. But if the 

 selectionists have thus changed their ground and taken 

 up new lines of defence, this does not concern us here. 

 The question is, whether their new line of defence is valid 

 and tenable or not. It appears to me, that if natural 

 selection took any share in the development of man 

 from some lower form of life, the argument is valid. 

 A power of articulation is a sine qua -non if a race of 

 speakers is to be evolved; and unless natural selection 

 be ruled out altogether, the congenital nature of this 

 power, and some instinctive manifestation of it, is just 

 what may be fairly expected on Darwinian grounds. On 

 the other hand, if use-inheritance be operative, this again 

 is, as Eomanes says, just what may be expected on 

 Lamarckian grounds. In fine, here, as in so many cases, 

 we have nothing which can conclusively decide between 

 the rival hypotheses. "What we have is the sort of thing 

 that may be due to one or other or both, if both be 

 established as vera causa. 



Dr. Arbuthnot Lane * has expressed his belief that 

 certain occupations, such as shoe-making and coal-heaving, 

 produce recognizable effects upon the skeleton and other 

 parts, and that these effects are inherited, being more 

 marked in the third generation than they were in the 

 first. And Sir Wm. Turner informed Prof. Herdman that 

 in his opinion, the peculiar habits of a tribe, such as tree- 

 climbing among the Australians and the inhabitants of the 

 interior of New Guinea, not only affect each generation 

 individually, but have an intensified action through the 

 influence of heredity. The inference may be drawn that 

 with acquired structure acquired habits would be trans- 

 mitted. But of this there is, so far as I know, but little 



* " Journal of Anatomy and Physiology," vol. xxii. p. 215. 



