i6o 

 THE DOG. 



374. The dog, like other domestic animals, has both a temporary and 

 a permanent set of teeth, divided into incisors, canines, anterior pre- 

 molars, pre-molars, and molars. The milk teeth are 12 temporary 

 incisors (six above and six below, in front of the jaw), four temporary 

 canine teeth or tusks (two above and two below, one on each side, the 

 upper as a rule being the strongest), and 12 temporary pre-molars, the 

 three first on each side of the upper and lower jaws. On the completion 

 of the dentition there are 42 permanent teeth in all (see par. 345), 

 viz. : 12 incisors (|-), four canines or tusks (f), four anterior pre- 

 molars (I), 12 pre-molars (f), and 10 molars (|). The premolars, 

 sometimes called false molars, are slightly separated from each 

 other, and are cone-shaped and pointed in the middle. The last 

 temporary pre-molar, or the fourth tooth from the tusk on the upper 

 jaw, is the largest and strongest, and is closely connected behind 

 with the two true molars, which have flat crushing crowns. The fifth 

 tooth from the tusk or first permanent molar on the lower jaw is the 

 largest tooth in the mouth, and a composite tooth. Anteriorly it is 

 cone-shaped and pointed, hke the pre-molars, while the posterior part 

 is flat and crown-shaped, like a true molar. The two last teeth are 

 true molars, and have flat crushing crowns. In some cases there are 

 se\en on each side of the upper jaw as well. 



375. A puppy has no teeth at birth, but their outline is seen on the 

 gums. The larger breeds of dogs generally cut their teeth sooner 

 than the smaller types, but the time within which the teeth are cut 

 and shed varies very much according to the breed. The first tooth to 

 make its appearance is usually the second pre-molar in the lower 

 jaw, and this occurs on or about the 20th day after birth. The other 

 teeth, incisors, tusks, and pre-molars follow in quick succession, so that 

 about the fifth week after birth all the milk teeth are in view. As a rule, 

 the lower temporary or milk teeth are cut before the upper, but the 

 reverse is the case with the permanent teeth. When the puppy is 

 three and a half months old, the temporary or milk teeth fall out, and 

 are replaced by permanent teeth, which process takes from four to six 



