TEETH. 



230 



TEETH. The last upper molar is double rooted, and its crown 

 directed backward. All the other molars are single-rooted, with 

 a slight median longitudinal groove on the outside. Their 

 crowns are irregularly conical, pointed, and jut out over their 

 contracted necks ; inner side of the crowns hollowed. Surface 

 of the crowns roughened with minute longitudinal grooves and 

 ridges. The upper molars have no trace of the supplemental 

 points to the crowns seen in many species of this family. The 

 lower molars, particularly the third and fourth, have very 

 slight accessory cusps. Necks of the molars uniform in size 

 with the upper part of the fangs. Fangs of the molars gradu- 

 ally tapering, those of the first and second upper much curved 

 inward; that of the third less so; that of the fourth straight; 

 the two fangs of the fifth are directed abruptly forward, the 

 posterior one much the smaller. Canines of both jaws very 

 large; the upper, however, much the larger; the lower more 

 curved. Of the six incisors of the upper jaw, those of the 

 outer pair are much larger than the middle ones, twQ-thirds 

 as long as the canines, and much like them in form. The mid- 

 dle ones have their antero-posterior diameter nearly twice their 

 lateral diameter, and their crowns are divided transversely. 

 The fangs of the inner pair are slightly bifid. Of the four 

 lower incisors, the outer are much the longer. * 



Measurements of the Tceth.\ 

 A. TEETH OF THE UPPER JAW. 



* For figures of the teeth, see Bull. Mus. Comp. Zool., vol. ii, pi. i, figg. 

 5-5 e (one-half natural size). 



t These measurements are taken from a middle-aged specimen, in which 

 the dentition is perfect and normal. In old age many of the teeth are usually 

 broken, and a portion of them often entirely wanting, through loss from 

 accident. As the lower canines could not be removed without removing a 

 portion of the jaw, they have not been fully measured. 



i The distance from the crown to the alveolus. 



$ The portion of the tooth inserted in the jaw. 



|| At the base of the crown. 



