THE ALLIES OF THE SQUIRREL: MAMMALIA 421 



one of several wolves or jackals, or a mixture of several 

 species. The great length of time since the dog first became 

 the companion of man, and the numerous races which have 

 arisen, render the question extremely complicated. 



Of our smaller wild carnivores none is more generally 

 known and feared than the skunk (Mephi'tis), of which there 

 are many species in the United States. Their powerful means 

 of defense is a pair of glands secreting a strong-smelling fluid, 

 which they are able to eject for a distance of several feet. 

 Though they are destroyed by the farmer for robbing his 

 hen-roosts, they are on the whole beneficial, as they feed 

 largely on injurious insects. Those who have observed them 

 most say that they make interesting and cleanly pets, even 

 without the removal of the scent-glands, and that they are 

 not prone to defend themselves except under great provoca- 

 tion. The presence of this means of defense has had its effect 

 upon the skunk's character, insomuch that if a person comes 

 upon it in the daytime it is likely to make no special effort 

 to escape, but goes about its business leisurely, secure in the 

 confidence that it will not be molested. The eastern species 

 are black animals about the size of a cat, with prominent white 

 stripes down the back and a white patch on the forehead. The 

 white markings on the black ground are usually cited as an 

 example of warning coloration. It has been asserted that it is 

 advantageous to the skunk to be thus marked, for if it had 

 a uniform black color, it might be mistaken in the uncertain 

 light for other night-prowlers and be pounced upon and killed 

 by an enemy before it had an opportunity to use its peculiar 

 method of defense. 



Among the aquatic carnivorous forms the Alaskan fur-seal 

 (Callota'ria alasca'nus) has been the subject of international 

 discussion on account of the value of its fur as an article of 

 commerce. This is a truly migratory species of mammal, 

 bringing up its young on the Pribilof or Fur-Seal Islands in 



