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- 
palatine 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 
Fic. 646.—Dissection oF Heap oF Horse. 
The masseter and superficial muscles and the parotid gland are in great part removed. a, a, Levator labii superi- 
oris proprius; 5, 6, levator nasolabialis; c, dilatator naris inferior; d, buccinator; e, common mass of buccinator and 
depressor labii inferioris; f, depressor labii inferioris; g, masseter; h, orbicularis oeuli; %, temporalis; &, occipito- 
hyoideus; &’, occipito-mandibularis; /, sterno-cephalicus; l’, tendon of same; m, omo-hyoideus; n, erico-pharyngeus; 
o, mastoid tendon of brachiocephalicus; p, splenius; q, inferior buccal and labial glands; r, superior buccal glands; 
$, remnant of parotid gland; ¢, mandibular gland; u, anterior cervical lymph glands; », probe passed into diverticulum 
nasi; w, cornu of alar cartilage; x, medial palpebral ligament; y, wing of atlas; z, scutiform cartilage of ear; /, lateral 
nasal nerve; 2, anterior nasal nerve; 3, superior labial nerve; 4, anterior part of superior buccal nerve; 5, buccinator 
nerve; 6, 6’, inferior alveolar nerve; 6”, mental nerve—continuation of 6; 7, masseteric nerve; S§, facial nerve (cut); 
9, superficial temporal nerve; 10, anastomosis between 9 and 8; 11, internal auricular nerve; 12, posterior auricular 
nerve; 13, digastric nerve; 14, cervical branch of facial nerve (cut); 15, auriculo-palpebral nerve; 16, lacrimal nerve; 
17, frontal nerve; 18, 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, masseterie artery; 26, great (posterior) auricular artery; 27, external branch 
of 26; 28, deep auricular artery; 29, anterior auricular artery; 30, transverse facial artery; 31, facial artery; 23, inferior 
labial artery; 33, superior labial artery; 34, lateral nasal artery; 35, dorsal nasal artery; 36, 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; 45, stump of great auricular vein; 46, ramus of 
mandible; 47, facial crest; 48, zygomatic arch; 49, 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. nasalis 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 
