OSTEOLOGY AND ARTHROLOGY 



115 



bone and ends at the external orbital process of the latter 

 bone. 



These crests, known as the parietal or temporal crests, 

 recall both in position and relations the temporal curved 

 line of the parietal bone of man. They contribute, as in 

 the case of the latter, to the formation of the boundaries 

 of the temporal fossa. 



In the carnivora, these crests are situated, throughout their 



f^.Cuves^ 



Fig. 60. — Skull of the Dog : Left Lateral Aspect. 



I, Posterior surface of the occipital bone ; 2, external occinital pro- 

 tuberance ; 3, occipital condyle ; 4, jugular process ; 5, parietal bone ; 

 6, frontal bone ; 7. orbital process ; 8, orbital cavity ; 9, external auditory 

 canal, in front of which is found the zygomatic process ; 10, tympanic 

 bulla ; II, superior maxillary bone ; 12, intermaxillary or incisor bone ; 

 13, nasal bone ; 14, anterior opening of the cavity of the nasal fossee ; 

 15, malar bone ; 16, lachrymal bone ; 17, inferior maxillary bone ; 18, con- 

 dyle of the inferior maxillary bone ; 19, coronoid process ; 20, incisor 

 teeth ; 21, canine teeth ; 22, molar teeth. 



J 



whole length, in the median line, the temporal fossae being, 

 accordingly, as extended as they possibly can be. In certain 

 species, the development of these crests is such that they 

 form by their union a vertical plate, which, in separating the 

 two temporal fossae, gives them a greater depth. In the pig, 

 the parietal crests, analogous in this respect to the temporal 

 curved lines of the parietal bones of man, are separated by^ 



8—2 



