THE SKULL AS A WHOLE 



77 



the premaxilla, and the facial parts of the lacrimal and malar bones. Its contour 

 IS approximately triangular, the base being posterior. It offers two principal 

 features. The facial crest extends forward from the ventral margin of the orbit, 

 and ends abruptly at a point about an inch and a quarter (ca. 3 to 3.5 cm.) above the 



Fig. 50. — Ventral Surface of Skull of Horse, Posterior Half Without Mandible. 

 The skull is inclined slightly. (Notation on key Fig. 49.) 



third or fourth cheek tooth ;^ its ventral aspect is rough for the attachment of the 

 masseter muscle. The infraorbital foramen is situated in a transverse plane about 

 an inch (ca. 2 to 3 cm.) in front of the end of the crest and about two inches (5 cm.) 



1 This relation varies with age. In the new-born foal the posterior part of the second tooth, 

 in the young horse the posterior part of the third tooth, in the older subject the fourth, hes below 

 the end of the crest. 



