THE HEAD. 



57 



Fig. 28. 



face. It is particularly distinguished by : 1, Its great thickness. 2, The osseous 

 conical cores which support the horns. These eminences, more or less long and curved, 

 very rugged, perforated by foramina, and grooved by tmall vascular channels, are 

 detached outwards from each side of the bone, near the summit of the head. The 

 processes which form the orbital arches rest by their summits on the zygomatic bone. 

 The supra-orbital foramen is transformed into a veritable and frequently multiple canal; 

 its anterior orifice opens into a vasculo-nervous groove, which ascends towards the base 

 of the horns, and descends to near the lower border of the bone. Between this groove 

 and the base of the orbital arch is the frontal boss. The orbital foramen entirely belongs 

 to this bone. The inferior border is deeply notched in its middle to receive the nasal 

 bones , the frontal sinuses are prolonged into the horn-cores, the parietal bone, and even 

 into the occipital bone. 



In the Sheep and Goat, the frontal bone is relatively less extensive and strong than in 

 the Ox ; it does not ascend to the summit of the head, and the frontal sinuses are not 

 prolonged beyond its superior border. 



4. Ethmoid bone. In ruminants, 

 the great ethmoidal cell is enor- 

 mously developed, and looks like a 

 third turbinated bone prolonged be- 

 tween the usual two; it has been 

 named the olfactory antrum. 



The ethmoid bone is closely im- 

 prisoned between the adjacent bones, 

 in consequence of the slight develop- 

 ment of the sinuses around it. This 

 character otherwise belongs to all 

 the domesticated animals, except soli- 

 peds. 



5. Sphenoid bone. In the Ox, 

 the subsphenoidal or pterygoid pro- 

 cesses are large and thin. The sub- 

 sphenoidal canal is absent. The 

 sella turcica is deep, and the bony 

 projection separating it from the 

 basilar process is very high. The 

 three suprasphenoidal canals are 

 converted into a single, but wide 

 one. There are no notches in the 

 superior border for the passage of 

 the internal carotid and spheno- 

 spinous arteries. That for the in- 

 ferior maxillary nerve is converted 

 into a canal the oval foramen. 



In the Sheep, the osseous promi- 

 nence that limits the pituitary fossa 

 posteriorly forms a lamina curv- 

 ing forwards and prolonged at its ex- 

 tremities into two points, which 

 constitute the posterior clinoid pro- 

 cesses. 



6. Temporal bone. In the Ox, RAM'S HEAD; ANTERIOR FACE. 



Sheep, and Goat,the tuberous portion 1? Occipital bone ; 2, Parietal bone ; 3, Core of right 

 ot the temporal bone is always con- frontal bone ; 4, The left core covered by its horn ; 

 sohdated with the squamous portion, 5? Superciliary foramen; 5', Channel descending 

 and the summit of the zygomatic f r0 mit; 6, Lachrymal bone; 7, Zygoma; 8, Nasal 

 only articulates with the ^one; 9, Supermaxillary bone; 10, Premaxillary 

 malar bone. bone; 10', Its internal process; 11, Incisive open- 



In the Ox, the condyle of the ing. 

 zygomatic process is very wide and 



convex in every sense. The parieto-temporal canal is very large and entirely excavated 

 m the temporal bone ; its superior or internal extremity opens above the petrous portion 

 in an excavation which represents the lateral cavity of the parietal protuberance in the 

 Hor>e ; at its inferior extremity it always shows several orifices. 



The mastoid process is very salient, and belongs to the squamous portion. The 

 mastoid crest is confounded with the upper root of the zygomatic process ; inferiorly, it 



