76 EQUINE AN^ATOMY. 



Action : Dilatator of the entrance of the nasal fossa. 



11. Maxtllo-labialis. Synonyms. Depressor labii 

 inferioris, (P). Inferior maxillo labialis, (L). Attach- 

 ments : Anterior border of the lower jaw and the skin 

 of the lower lip. Action : Pulls the lower lip down 

 directly or on one side. 



12. Mento-labialis. — Forms the base of the ronnded 

 protuberance beneath the lower lip. No bony attach- 

 ment. 



13. Middle (intermediate) posterior. — Synonyms. 

 Levator menti, (P). Incisive muscle of the lower lip. 

 (L). Attachments : External surface of the body of 

 the lower jaw and to the mento-labialis. Action : 

 Elevator of the lower lip. 



Masseterine Region.— Five muscles. 



1. Masseter. — Synonyms. Zygomatico-maxillaris, 

 (G:). Attachments : Zygomatic crest, upper half of 

 external surface of inferior maxillary branch. Action: 

 Elevator of the lower jaw. 



2. Temporal. — Synonyms. Temporo-m axillaris, (G). 

 Attachments : Temporal fossa, orbital hiatus, coronoid 

 process and anterior border of the branch of the lower 

 jaw. Action : Elevates the jaw. 



3. Internal pterygoid. — Synonyms. Pterygoid- 

 eus internus, (P). Attachments : The palatine crest, 

 subsphenoidal process, hollow of the internal face of the 



