THE TEETH. 87 



ing the corresponding milk teeth ; premolars or bicuspids, 

 replacing the milk-molars; and three true molar teeth on 

 each side in each jaw, which are not preceded by any 

 deciduous or milk teeth. 



Fig. 48. TEMPORARY AND PERMANENT TEETH in the jaws of a 

 child six years old. The temporary teeth are all still present, 

 and the crowns of the corresponding permanent teeth are formed; 

 the first molars have appeared, and behind them are the second 

 molars with the divisions between the fangs in process of forma- 

 tion. 



The incisor and canine teeth are simple, each having only 

 one fang and one prominence of the crown; the crowns of the 

 incisors being chisel-shaped, while those of the canines come 

 to a point or cusp. The premolar teeth get the name of bicuspid 

 because the crown of each has two cusps, an inner and an outer; 

 their fangs likewise, especially those of the anterior pre- 

 molars, have a tendency to divide towards the extremity. 

 The molar teeth, both milk-molars and true, have the ex- 

 tremity of the crown thrown into several elevations, and are 

 said to be multicuspid. Those of the upper jaw have three 

 fangs, two on the outside, and one directed inwards. Those 

 of the lower jaw have only two fangs, one in front of the 

 other, but they are double fangs, that is to say, they are 



