TEETH IN THE PIG. 159 



posterior teeth, which are not displaced by vertical successors, 

 are the " molars," properly so called.* 



" The hog is one of the few existing quadrupeds," says Owen, 

 " which retain the typical number and kinds of teeth. Ex- 

 amples of the typical dentition are exceptions in the actual 

 creation ; but it was the rule in the forms of mammalia first 

 introduced into this planet, and that, too, whether the teeth 

 were modified for animal or vegetable food/' 



In the pig the teeth are numerous more numerous than in 

 man or in the horse the permanent teeth amounting to forty- 

 four. These forty-four permanent teeth are equally divided 

 between the upper and the under jaw, so that there are 

 twenty-two teeth in each. The twenty-two teeth in each jaw 

 consist of incisors, canine or tusks, premolar or false molar, 

 and molar or true molar. The number of each kind is the 

 same in both jaws namely, six incisors ; two canine, one on 

 each side ; eight premolar, four on each side ; and six molar, 

 three on each side ; so that there are in all in the pig, of per- 

 manent teeth, twelve incisors, four canine, sixteen premolar, 

 and twelve molar. 



The incisors in the lower jaw, says Youatt, are long, round, 

 and nearly straight ; of those in the upper jaw, four closely 

 resemble the corresponding teeth in the horse ; while the outer 

 incisor on each side has some resemblance to the fleur-de-lis 

 shape of those of the dog. These last sometimes come so near 

 to the canine as to obstruct their growth. 



The seven molars on each side of each jaw namely, four 

 premolars and three true molars augment from before back- 

 wards so rapidly that the last has at least fifty times the bulk 

 of the first. The anterior teeth of these seven are of a more 

 simple configuration than the posterior, being flattened laterally 

 and pointed in the middle. The posterior present four, and the 



* Owen. 



