Dissection of Sheep^s Head. 215 



section we come upon the termination of the second branch, 

 viz., the Superior Maxillary, which, after leaving the cranium 

 together with the Ophthalmic through the Sphenoidal fissure*, 

 crosses the lower part of the Zygomatic fossa, enters the 

 maxillary hiatus, passes through the infra -orbital canal, and 

 emerges on the face at the infra-orbital foramen, where we 

 now find it dividing into numerous facial branches, especially 

 nasal and labial, and in close relation with the ultimate 

 fibres of the temporo-facial nerve. 



The anterior inch and a half of the body of the inferior 

 maxilla should be carefully examined (especially about an 

 inch behind the teeth), for the anterior appearance of the 

 dental nerve through the mental foramen : that nerve, namely, 

 which traverses the dental canal in the inferior maxilla ; 

 entering the canal by the dental foramen, an opening 

 one inch below the sigmoid notch on the inner side of the 

 maxilla. The Dental Nerve is the largest of the three 

 branches of the Inferior Maxillary Division of the Fifth Nerve. 



The Temporal muscle above the cartilage of the Ear should 

 next be cleaned, and its origin from the parietal ridge, part 

 of the occipital crest, and zygomatic process, noted ; as also 

 its insertion into the coronoid process of the inferior maxilla, 

 which will be found about an inch and a half behind the orbit. 



If the Student will place a loose ramus of a sheep's jaw 

 on his dissection in its proper position, he will be better able 

 to make out the situation of the condyle, coronoid process, 

 neck of condyle, ramus, &c., and the points of attachment 

 of the Temporal and Masseter muscles. 



And here (as in all Herbivora) he may note that the 

 muscles more directly worked in mastication, e.g., the Mas- 

 seter and the Pterygoids (to be seen hereafter), are propor- 



* In Man, tlie Ophthalmic leaves by the Sphenoidal fissure, and the Superior 

 Maxillary by the foramen ovale. 



