SWINE. 277 



(5) They eat flesh, but do not seek to capture living ani- 

 mals for food. 



(6) They naturally resort to watery places in which to 

 wallow. 



(7) They produce a number of individuals at one birth. 



(8) Their senses of smell and hearing are peculiarly 

 acute, and 



(9) The peculiarities of voice are very similar. 



IV. The various species of the true wild hog 

 (Sus aper) have the following characteristics in 

 common : 



(1) They are swift of foot and fierce in disposition. 



(2) The males are possessed of enormous tusks. 



(3) They are more easily tamed if captured when young. 



(4) When matured they are solitary in their habits. 



(5) They are nocturnal in their habits of feeding. 



(6) The young are longitudinally striped for a time, and 



(7) The sows suckle their young for many weeks and 

 defend them for a long period after they are weaned. 



V. It is now pretty generally conceded that 

 the domestic varieties are descended from the wild 

 species, as 



(1) The general anatomy is the same and the form and 

 general outline bear a somewhat close resemblance. 



(2) The period of gestation is the same in both ; they can 

 be successfully bred together and there is a general resem- 

 blance in the habits. 



VI. Under domestication the following are 

 some of the changes that take place : 



(1) The ears become less movable, the tusks and muscle:? 

 of the neck diminish in size, the back and sides lengthen, the 

 flank and hindquarters deepen, the body becomes less capa- 

 cious, the limbs grow shorter, the bristles are partially or 

 wholly removed, and the animal becomes much less active. 



(2) The stomach and intestines enlarge, they desire more 

 food and the tendency to obesity increases. 



(3) The male loses the solitary habit, the female breed? 

 -more frequently and has larger litters, and they seek their food 



in the day. 



VII. The domesticated species have been 

 known to revert to the wild state, as is witnessed by 



