34 



be accepted as a fact, must be understood to be 

 absolutely separated from atavism and variation ; on 

 the other hand, if it only- remain a hypothesis, it is 

 difficult to say what is atavism and what is telegony, 

 or to deny that both terms are identical in their 

 application. Instead of reversion and variation being 

 always consequent upon the entrance of disturbing 

 influences in the line of heredity, they are probably 

 just as likely to occur from outside influences in 

 environment, whether gradual or violent, during the 

 impressionable period of gestation. 



Violent crossing is instrumental in producing 

 many reversions and variations, and in arresting 

 fecundity. This is exemplified in unfertile hybrids 

 of all species, but this is probably more the experience 

 of fanciers than regular commercial breeders ; and, 

 although " like begets like," it is impossible to forecast 

 the results when violent crossing is resorted to, as 

 the type of progeny may radiate in all directions 

 except the one desired. This is naturally a domestic 

 observation, because the rigorous law of nature pre- 

 cludes this intermingling amongst animals in a wild 



state. 



The law of " the survival of the fittest," it is 

 said, operates in the latter circumstances, and main- 

 tains each species in strength and purity, although, 

 on the authority of the late Duke of Argyle in 

 " Evolution Cross-examined," there is no more barren 

 phrase in existence than that coined by the late Mr 

 Herbert Spencer. It can only be understood as a 



