100 



COMPARATIVE OSTEOLOGY;, 



to the shape of the horns, which they support. These are the flints or horn 

 cores, which are porous in their structure, especially at the roots f they are very 

 rough, covered by thick periosteum, and contain sinuses, large canals, and 

 foramina, through which pass arteries and veins, and wliich are continuous 

 with the largely-developed frontal sinuses ; the latter extend from the orltit 

 to the extremities of the cores, and nearly as far backwards and downward* 

 as the foramen magnum. The superior surface of the frontal bone is flat and 

 broad, especially in the male. The supraorbital foramina are double, placed 

 very far backwards, and continued by a groove which extends backwards and 

 forwards. ^The frontal arch articulates with the malar portion, of the zygoma^ 



Fic. 20. 



SKTLL OF AN OX.— Superior Aspect. 

 a. Frontal] crest; b, Lateral crest; c c c, Horn ctfre. 

 d, Nasal peak ; e. Supraorbital foramina: .BoNES :— 

 1. Frontal ; 2» Lachrymal ; 3 Malar ; 4. Superior maxil. 

 lary: 5. Nasal; 6. Premaxilla, with Incisive-openings. 



^he parietal bone is transversely elongated, and recurved at its extremities^ 

 It is placed below the frontal crest, extending under and supporting the cores,: 

 and entering the temporal fossa to articulate with the sphenoid and temporal 

 bones. Beneath the crest posteriorly it forms with its fellow the inter-parietal 

 suture. 



The Wormian bone exists, fused with the occipital and parietals. It is 

 described as " wanting," by some authorities. 



The occipital bone is not visible when the skull is viewed superiorly, being 

 concealed by the prominent t^ontal crest. It is much wider from side to side, 

 but smaller than in the horse. It has neither crest nor tuberosity, the condyles 

 being less prominent, but wider ; the styloid processes are shorter, but broader, 

 and curved inwards. The basilar proce.ss is short and thick, with a large 

 basilar groove, and two rough prominences for m uscular attachment anteriorl 3? ■ 

 The condyloid foramina are double, sometimes triple. 



