1897. HUMAN EVOLUTION. 189 



generation, which is, in fact, a necessity of ontogenetic recapitulation. 

 And it must be confessed that palaeontologists have exceptional 

 facilities for observation. 



Mr. Reid speaks of " spontaneous variations, caused we know not 

 how " (p. 12). True, we may not know how all variations are caused ; 

 but this is no reason for regarding any as spontaneous. It seems 

 safer to suppose that all variations could, if our knowledge were 

 sufficient, be traced to some cause in the environment. For instance, 

 the crumpling of our toes is assumed to result from the wearing of 

 boots. And the character is transmitted. Two of my children, born 

 with straight-toed feet, which would not disgrace a savage, and kept 

 bare-footed for this very observation, showed a crumpling in of the 

 toes before boots were taken to at all. 



There are other causes of variation. I have noted in my own 

 children that a short period between one birth and another has 

 unfavourably influenced the offspring ; that change of scene by the 

 mother has been favourable ; that a vegetarian diet during gestation 

 produced a very small child; that change back to a meat diet produced 

 the largest child of the family ; and lastly, visits to the Inventions 

 Exhibition by the mother during the period of gestation resulted in a 

 child which, unlike the others, has shown, since infancy, a remarkable 

 mechanical proclivity. Now such variations might by a casual 

 observer be called "inborn " ; they would be classed as " spontaneous 

 variations, arising we know not how." 



Mr. Reid does believe in the transmission of acquired characters 

 in the case of unicellular organisms (p. 134), and this, perhaps, 

 explains the whole matter. The germ is a unicellular organism, and 

 therefore it should be modifiable in accordance with its environment. 

 Such environment would be different in the body of a sedentary clerk, 

 and a hard-working agricultural labourer ; and on this hypothesis 

 the offspring in these cases would be different. 



In the special section (Part II.) of his book, Mr. Reid first deals 

 with man's evolution against disease. He says that man improves in 

 the face of disease, that the more he is tried by it, the more he is able 

 to resist, that races which have never known particular diseases, such 

 as measles, are killed, like flies on the approach of winter, by what is 

 to us a mild complaint. This looks remarkably like inheritance of 

 acquired characters. Mr. Reid says it is due to elimination of the 

 unfit. But that, if it were the sole cause, should leave a race better 

 able to resist disease all round. This is not the fact ; it is only 

 the individual that is better equipped against such diseases as he has 

 had particular struggles with. This seems as though he were 

 influenced by each struggle, and as if his disease-resisting powers 

 acquired, by use, greater strength of coping with those diseases of 

 which they had knowledge, while not resisting those in which they could 

 get no training ; and these characters are transmitted to offspring. 



In dealing with man's evolution against stimulants, the author 



