292 WILD TRAITS IN TAME ANIMALS. 



of their traditional enemies ; although this would 

 only be true if we traced the origin of their 

 instincts back to an extremely remote period. 

 One finds that among many animals certain 

 inherent antipathies exist, some of which are 

 undoubtedly traceable to legends of infinite 

 antiquity. Thus the horror that most warm- 

 blooded creatures have of snakes and other 

 reptiles is probably traceable to the time when 

 the only mammals existing were the humble 

 little marsupials whose remains we find in the 

 Stonesfield slate and Oxford clay. During the 

 Cretaceous period the whole world was swarming 

 with voracious reptiles from the size of a house 

 to the size of a sparrow ; and undoubtedly the 

 feeble mammals must have needed all the extra 

 quickness of movement and wit which their tour- 

 chambered hearts and higher nervous organisa- 

 tion gave them in escaping such terrible foes. 

 In the long-run the mammals proved victorious ; 

 but throughout an immense epoch the strife must 

 have been of the most fierce and deadly character. 

 To such causes we may fairly attribute that innate 

 antipathy which we feel to reptiles and all cold 

 and crawling things. The hostility existing 

 between cats and dogs is shown to be innate 





