Introduction 33 



The enemies of each species should be considered and enemies 

 gauged with care. The struggle for life is at all times so bitter ease^^^' 

 that each species is barely able to hold its own, has all the 

 burdens it can bear (a thought that has its meed of comfort 

 for us); a trifle more of destruction and down it goes, a trifle 

 less and it spreads mightily. 



Parasites are sometimes to be enumerated as disease. The 

 kinds and the modes of combating them are important. But 

 all parasites are not enemies. The species of fly which pupates 

 in the dung of the Grizzly-bear is as likely to be a friend as a 

 foe. 



One of the most interesting and obscure traits ob- odd 

 served in wild animals is their unexpected friendships. The ner- 

 British Badger is known to share its den occasionally with ^"'^^ 

 the Fox, and the Fox with the Rabbit. Instances are 

 here given of a friendship between a Badger and a lost 

 child, a Badger and a Coyote, also of a Red-squirrel and an 

 Acadian owl. • 



Whatever the explanation, it is always gratifying to 

 find that any animal has reached a plane above the purely 

 carnal. 



Strange comradeships and parasitism are on opposite com- 

 sides akin to commensalism. Of this nature is the habit seen salism 

 in some Mice, of quartering themselves on the hoards of certain 

 Ground-squirrels. 



Many cases not easily classed will come to mind. For 

 example, the Water-shrew that lives in the Beaver house, the fly 

 that pupates in the Bear's dung, the beetles that live in the filth 

 at the bottom of a Red-squirrel's nest. 



Quadrupeds are supposed to live from four to five times age 

 as long as the time they need to attain maturity. Their life is 

 three parts, youth, prime and age. Many facts in line with 

 this belief are adduced, as well as all available data fixing the 

 normal life term of each species. 



