128 WILD TRAITS IN TAME ANIMALS. 



heritance or non-inheritance of acquired charac- 

 ters is finally settled in the negative. Weismann's 

 elaborate theory, as at present set forth, seems to 

 me to involve much which belongs rather to the 

 region of metaphysics than to that of physiology. 

 We must wait until we have acquired many more 

 solid facts upon which to base our arguments if 

 we are to attack the Heredity Problem in the 

 way in which Darwin attacked that of the Origin 

 of Species. But without doubt there is a growing 

 tendency amongst men of science to discounte- 

 nance the once common doctrine that the educa- 

 tion of one generation, whether among animals or 

 men, has an effect upon the mental attributes of 

 the next. 



Most animals have an inbred horror of lizards 

 and snakes, and this instinct is almost certainly a 

 vestigial echo of the long and deadly struggle for 

 supremacy between the warm- and cold-blooded 

 populations which must have gone on without 

 intermission for many thousands of generations. 



There was a time when, as Tennyson saj^s — 



"A monstrous eft of old 

 Was lord and master of earth," 



and when the largest mammals were miserable 



