56 



THE BONES, 



protuberance is obtuse, and gives rise on each side to the superior curved lines ; in the 

 Sheep, these curved lines are very salient and occupy the summit of the head. 



The styloid processes are short and much bent inwards. The ba.silar process, wide, 

 short, and thick, has a groove in the middle of its external face ; this groove is sometimes 

 absent in the Sheep and Goat. 



The condyloid foramina are double, sometimes triple ; the superior foramen does not 

 pass directly into the cranium, but goes to a vast conduit that opens behind on the lateral 

 margin of the occipital foramen, and which terminates in front by two orifices, one 

 entering the parieto-temporal canal, the other opening on the external surface of the 

 bone. The foramen lacerum is divided into an anterior and posterior foramen by the 

 mastoid portion of the temporal bone. 



Parietal bone. The parietal bone in the Ox does not occupy the anterior aspect 



Fig. 27. 



ox's HEAD; ANTERIOR FACE. 



1, Mastoid process; 2, Superciliary, or supra-orbital foramen; 3, Zygoma; 4, 

 Lachrymal bone j 5, Maxillary spine ; 6, Inferior orifice o 



f the supermaxillo-dental 



canal. 



of the head, but concurs with the occipital to form the base of the neck. It represents a 

 very narrow osseous plate, elongated transversely, and curved at its two extremities, 

 which descends into the temporal fossae to rest upon the sphenoid bone. There are no 

 parietal ridges. The internal protuberance is only marked by a slight elevation of the 

 internal plate ; for the most part it belongs to the occipital bone. 



The parietal bone of the Ox is developed from three centres of ossification, and the 

 middle nucleus is even primarily divided into lateral halves ; but these centres are 

 consolidated with each other at an early period, as well as with the anterior portion of 

 the occipital. It does not aid in the formation of the parieto-temporal canal, and is 

 excavated internally by cavities which communicate with the frontal sinuses. 



The parietal bone of the Sheep and Goat is relatively much larger than that of the Ox. 

 It participates in the formation of the parieto-temporal canal, and has no sinuses. 



3. Frontal bone. In ruminants, the frontal bone does not respond to the temporal 

 and palate bones. 



In the Ox, this bone is extremely developed, by itself occupying the anterior half of the 



