THE TRIGEMINAL NERVE 



797 



the lateral canthus and ramify chiefly in the lower lid and the adjacent skin. Anas- 

 tomoses are formed with branches of the lacrimal nerve. 



2. The sphenopalatine nerve (N. sphenopalatinus) is given off in the pterygo- 

 palatme fossa from the ventral border of the maxillary nerve (Fig. 564). It is 

 broad and flat and forms a plexus in which several small sphenopalatine ganglia 



Fig. 646. — Dissection op Head of Horse. 

 The masseter and superficial muscles and the parotid gland are in great pa-rt removed, a, a. Levator labii superi- 

 oris proprius ; 6, 6, levator nasolabialis; c, dilatator naris inferior; d, buccinator; e, common mass of buccinator and 

 depressor labii inferioris; /, depressor labii inferioris; g, masseter; h, orbicularis oculi; i, temporalis; k, occipito- 

 hyoideus; k', occipito-mandibularis; I, sterno-cephalicus; V, tendon of same; m, omo-hyoideus; n, crico-pharyngeus; 

 o, mastoid tendon of brachiocephalicus; p, splenius; g, inferior buccal and labial glands; r, superior buccal glands; 

 s, remnant of parotid gland; t, mandibular gland; u, anterior cervical lymph glands; v, probe passed into diverticulum 

 nasi; lu, cornu of alar cartilage ; x, medial palpebral ligament; (/, wing of atlas; z, scutiform cartilage of ear; i, lateral 

 nasal nerve; 2, anterior naaal nerve; 3, superior labial nerve; ^, anterior part of superior buccal nerve; 5, buccinator 

 nerve; 6, 6', inferior alveolar nerve; 6", mental nerve — continuation of 6; 7, masseteric nerve; 5, facial nerve (cut) ; 

 5, superficial temporal nerve; iO, anastomosis between P and 5; 11, internal auricular nerve; 1^, posterior auricular 

 nerve; 13, digastric nerve; 14, cervical branch of facial nerve (cut); 15, auriculo-palpebral nerve; 16, lacrimal nerve; 

 17, frontal nerve; i5, infratrochlear nerve; 19, zygomatic nerve; 20, spinal accessory nerve; 21, ventral branch of 

 spinal accessory nerve (to sterno-cephalicus); 22, ventral end branch of first cervical nerve; 23, thyro-laryngeal 

 artery; 24, internal maxillary artery; 25, masseteric artery; 26, great (posterior) auricular artery; 27, external branch 

 of ^ff; ^5, deep auricular artery; ^P, anterior auricular artery; SO, transverse facial artery ; Si, facial artery; ^S, inferior 

 labial artery; SS, superior labial artery; S4, lateral naaal artery; 35, dorsal nasal artery; S^, angular artery of eye; 37, 

 terminal branches of superior labial nerve; 38, branch of buccinator artery; 39, buccinator vein; 40, vena reflexa; 42, 

 jugular vein; 43, external maxillary vein; 44, ventral cerebral vein; 4^, stump of great auricular vein; 4^, ramus of 

 mandible; -47, facial crest; 43, zygomatic arch; 4^, parotid duct. (After Ellenberger-Baum, Top. Anat. d. Pferdes.) 



are interposed. It divides into posterior nasal, and greater and lesser palatine 

 nerves. (1) The posterior nasal nerve (N. nasaiis aboralis) passes through the 

 sphenopalatine foramen, in which it bears one or more minute ganglia, enters the 

 nasal cavity, and divides into medial and lateral branches (Figs. 565, 588). The 

 medial branch (N. septi narium) runs forward in the submucous tissue of the lower 

 part of the septum nasi, gives twigs to the mucous membrane here and to the 

 vomero-nasal organ, passes through the palatine fissure, and ramifies in the anterior 



