188 AGE OF THE DOMESTIC ANIMALS. 



Four to Fourteen Days. — In the first two weeks the second 

 upper molar and the third lower molar appear. 



TiDO to Five Weeks. — During the next three weeks the 

 second lower molar, the third upper molar, and the pinchers 

 of both jaws accomplish their eruption. 



Five Weeks to Three Months. — At about six weeks the 

 intermediate incisors of the lower jaw appear, which are followed 

 in two weeks by the intermediate incisors of the upper jaw. 



Three Montlis. — At three months the eruption of the tem- 

 porary teeth is completed, and during the next few months the 

 teeth become more or less worn, according to the character of food 

 upon which the animal is nourished. 



Fig. 171. 

 Skull of a three-month-olcl pig with full milk dentition. 



SECOND PERIOD ERUPTION OF THE PERMANENT TEETH. 



About Six Months. — Before the first half-year the first per- 

 manent molar (fifth) and the first premolar (wolf-tooth) in each 

 jaw appear. 



Nine Months. — Within a month of three-quarters of a year 

 the corner incisors and the tusks make their eruption, followed 

 shortly by the second molars (sixth) of both jaws. 



Oiie Year. — At one year the lower pinchers protrude from 

 the gums, preceding the superior pinchers by two to three 

 months. At about this time, thirteen to fourteen months, the 



