50 



THE SKELETON OF THE HORSE 



Its lower part is perforated centrally by a large, almost circular opening, the 

 foramen magnum (Foramen occipitale magnum), at which the cranial cavity and 

 vertebral canal join. The foramen is bounded laterally and dorsally by the lateral 

 parts of the bone, and ventrally by the basilar part. Above the lateral parts — ■ 

 but not entering into the formation of the foramen magnum — is the squamous part. 



The lateral parts (Partes laterales)i bear the occipital condyles (Condyli oc- 

 cipitales), which articulate with the atlas. The condyles are obliquely placed, 

 wide apart dorsally, and separated ventrally by a small interval (Incisura inter- 

 condyloidea) . The articular surface is curved so sharply in the dorso-ventral 



Occipital Parietal Squamoxts temporal 



4- 



Lacrimal 



Maxilla 



Nasal 



Fig. 28. — Skull of Horse, Right View. 

 1, Occipital condyle; 2, paramastoid process; 3, mastoid process; 4, posterior process of squamous temporal bone 

 5, external acoustic process; 6, zygomatic process of temporal bone; 7, postglenoid process; 8, glenoid cavity of squamous 

 temporal bone; 9, condyle of same; 10, supraorbital process of frontal bone; 11, temporal part of frontal bone; 12, 

 orbital part of frontal bone; i5, fossa sacci lacrimals; i.^, orbital surface of lacrimal bone; ^5, lacrimal tubercle; 16, 

 zygomatic process of malar bone ; i 7, maxillary tuberosity; i5, facial crest; iP, infraorbital foramen; jSO, naso-maxil- 

 lary notch; 21, body of premaxilla; 21', nasal process of same; 22, body of mandible; 23, mental foramen; 24, 25 

 horizontal and vertical parts of ramus of mandible; 26, condyle of mandible; 27, coronoid process of mandible; 28 

 angle of mandible; 29, vascular impression; 30, interalveolar margin; 31, incisor teeth; 32, canine teeth; 33, hyoid 

 bone (great cornu). 



direction as to form a blunt ridge. The cranial surface is concave and smooth. 

 Lateral to the condjde is the paramastoid process (Processus paramastoideus),^ a 

 strong plate of bone which projects downward and backward; its lateral surface is 

 convex and roughened for muscular attachment; its medial surface is concave from 

 end to end. Between the root of this process and the condyle is a smooth depres- 

 sion, the condyloid fossa (Fossa condyloidea ventralis) ; in this is the hypoglossal 

 foramen (Foramen hypoglossi), which transmits the nerve of like name. 



The basilar part (Pars basilaris)' is a strong, somewhat prismatic bar, which 



1 Also known as the exoccipitals. ^ Also known as the styloid or jugular process. 



^ Also termed the basi-occipital or basilar process. 



