ii8 THE ARTISTIC ANATOMY OF ANIMALS 



portion, from which springs the zygomatic process, which 

 is directed towards the face, to terminate in the following 

 manner : in the carnivora, the pig, and ruminants, it 

 articulates with the malar bone by its inferior border ; 

 in the horse, it insinuates itself as a sort of wedge between 

 the malar bone and the orbital process of the frontal bone, 

 with which it articulates, as we have already pointed out, 

 and contributes, by a portion situated in front of this 

 articulation, to form the boundary of the anterior opening 

 of the corresponding orbital cavity. As in man, the zygo- 

 matic process arises by two roots : one, transverse, behind 

 which is situated the glenoid cavity of the temporal bone ; 

 the other, antero-posterior, which proceeds to join above 

 with the superior curved line of the occipital bone. 



Behind the glenoid cavity is found the external auditory 

 canal, and, further back still, the mastoid process. This 

 latter, but slightly developed in the carnivora, a little more 

 so in the ruminants, and still more in the horse, has its 

 external surface traversed by a crest, the mastoid crest, 

 which, after becoming blended with the antero-posterior 

 root of the zygomatic process, proceeds with this latter to 

 join the superior occipital curved line. 



Below the auditory canal is situated a round prominence, 

 highly developed in carnivora ; this is the tympanic bulla, 

 also called the mastoid protuberance ; it is an appendage of 

 the tympanum. 



The Face 



The bone of this region, around which all the others come 

 to be grouped, is, as in man, the superior maxillary. The 

 relations of this maxillary with the neighbouring bones is 

 not exactly the same in all animals ; for example, in the ox, 

 sheep, and horse, in which the bones of the nose are wide in 

 their upper part, and in which the lachrymal bone, which is 

 very highly developed, encroaches on the face, the superior 

 maxillary does not meet the frontal bone ; it is separated 

 from it by the above-named bones. It unites with it, on the 

 other hand, in the dog and the cat. In the bear, it is separated 

 from the bones of the nose by a small tongue of bone which 



