MYOLOGY 



239 



Transversus Nasi. — In the horse this muscle, which is 

 very thin, is situated on the dorsum of the nose, and pro- 

 ceeds to be inserted into the cartilaginous skeleton of the 

 nostrils. In the pig, it occupies an analogous situation. 

 It does not exist in the ox or in carnivora. The trans- 

 versus nasi is a dilator of the nostrils. 



Fig. 92. — Myology of the Horse : Muscles of the Head. 



I, Masseter ; 2, orbicularis palpebrarum; 3, zygomaticus major; 

 4, lachrymal (this muscle is sometimes described imder the name of the 

 small zygomatic) ; 5, external elevator (or deep) of the upper lip and ala 

 of the nose ; 6, internal elevator (or superficial) of the upper lip and of 

 the ala of the nose ; 7. levator anguli oris or caninus ; 8, orbicularis oris; 

 9, buccinator; 10, maxillo-labialis ; 11, zygomatico-auricularis ; 12, temporo- 

 auricularis externus ; 13, cervico-auricularis; 14, parotid gland ; i5,parotido- 

 auricularis ; 16, inferior maxillary bone. 



Caninus (Fig. 90 ; Figs. 7, 91, 92). — This is the muscle 

 called by veterinarians the great supramaxillo-nasal. 



In the dog and the cat it is situated below the inferior 

 border of the external elevator of the upper lip, of which it 

 follows the direction. It arises, as does this latter, from the 

 external surface of the maxilla, and goes also to terminate 

 in the upper lip by blending with the internal elevator 



