54 



ELEMENTS OF MAMMALIAN ANATOMY. 



beginning in a vertical groove, the lachrymal groove, car- 

 ries the duct permitting the tears to pass from the eye 

 into the nasal chamber (Fig. 16). 



The malar bone is paired. It forms the cheek as well 

 as the lateral and cephalic border of the orbit. The arch 

 largely formed by this bone is the zygoma. The process 

 projecting dorsad toward the postorbital process of the 

 frontal bone is the postorbital process of the malar. The 

 masseter muscle originates on the border of the malar. 



FIG. 19. MESAL OR INNER ASPECT OF THE MANDIBLE. 



ang, Angle ; cndyl, condyle ; cor pr, coronoid process ; can, canine tooth ; 

 inc, incisor teeth; inf. d. fm, inferior dental foramen; in, inferior 

 notch ; mol, molar tooth ; prm, premolar teeth ; dt, diastema ; sm, sur- 

 face of symphysis ; up, superior notch. 



The mandible or inferior maxillary is the single bone 

 forming the lower jaw (Figs. 17 and 21). It is made up 

 of two halves which are united by an immovable articula- 

 tion or symphysis (Fig. 19) at the chin. Each half con- 

 sists of a horizontal and an ascending ramus. On its 

 alveolar border the horizontal ramus bears three incisor 

 teeth, a canine, two premolars, and a molar tooth. In 

 the caudal part of the oral surface of this ramus is the in- 



