THE EXTERNAL CAROTID ARTERY 



549 



It detaches branches to the muscles and skin in the submaxillary space, the sub- 

 maxillary lymph glands, and the sublingual gland. It also gives off the small 

 submental artery, which runs forward superficially toward the lower lip, supplying 

 twigs to the skin and the mylo-hyoideus. 



Fig. 4.36. — Parotid, M,\ssf.teric, and Lingu.\i, Rkgions op Horse: Dekp Dissection, Third Layer. 

 a, Mylo-hyoiileus, anterior part, reflected; b. genio-hyoideus; c, genio-glos.sus; rf, sublingual gland; 



e. 



ramus of mandible, the greater part of which is removed; e', stump of ma.«seter; /, maxillary tuberosity; (j, great 

 eornu of hyoid bone; /(, wing of atlas; i, intermediate tendon of tligastricus; i' , anterior belly, i", posterior belly 

 of digastricus; k, posterior part of mylo-hyoideus; /, hyo-glossus; m, pterygoideus internus (cut); n, stylo-hyoideus; 

 (), stylo-maxillaris (cut); p, crico-pharyngeus; <y, ohlicjuus capitis ant.; i\ tendon of trachelo-mastoideus; 

 s, rectus cap. ant. major; /, niastoido-humeralis (cut); !/, sterno-cephalicus (cut); r, sterno-thyroideus 

 (cut) ; w, sterno-hyoideus (cut); x, omo-hyoideus; ,v, obliquuscap. post.; z, splenius (cut); 1-Jf, upper cheek teeth; 4' < 

 last cheek tooth; 5, stump of facial nerve; 6, stump of buccinator ner\-e; 7, lingual nerve; 7", superficial branch, 7", 

 deep branch of lingual nerve; 8, stumps of inferior alveolar artery, vein and nerve; 9, mylo-hyoid nerve (cut); 10, 

 glosso-pharyngeal nerve; 11, hypoglossal nerve; 12, superior laryngeal nerve; 73, ventral branch of first cervical 

 nerve; 14. vagus and sympathetic; 15, dorsal branch of spinal accessory nerve; 16, ventral branch of same; 17 , 

 inferior cerebral vein; /5, submaxillary duct; /9, common carotid artery; 50, parotid branch; 21, thyro-laryngeal 

 artery; 55, pharyngeal artery: 5.^, laryngeal artery; 54, internal carotid artery; 5-5, occijiital artery; 55, external 

 carotid artery; 37-31, external maxillary artery; 2S, posterior palatine artery; 29, lingual artery; SO, sub- 

 lingual artery; 32, internal maxillary artery; 33, internal maxillary vein (origin); 34, remnant of parotid gland; 

 35, thyroid gland; 36, jugular vein; 37, pharyngeal lymph glands. (After Ellenberger-Baum, Top. Anat. d. 

 Pferdes.) 



In some cases the sublingual artery arises from the lingual and the submental from the 

 external maxillary. Sometimes the sublingual remains on the external face of the mylo-hyoideus 

 — thus resembling the submental of man — and the sublingual gland is supplied by a special 

 branch of the lingual. 



Not uncommonly a considerable branch, given off in the submaxillary space, turns round 

 the lower border of the jaw and enters the middle of tlie lower part of the masseter muscle. In 

 some cases this artery is of large size and its pulsation can be felt. It is accompanied by a vein. 



(4) The inferior labial artery (A. labialis inferior) arises from the facial a little 

 before it reaches the depressor labii inferioris (Fig. 435). It passes forward, dips 

 under the depressor muscle, and continues to the lower lip. It supplies branches to 

 the muscles and skin in this region, to the inferior buccal glands, the mucous mem- 

 brane of the cheek, and the lower lip, anastomosing with the mental artery and the 

 corresponding vessels of the opposite side. It detaches a branch (A. anguli oris) 

 to the angle of the mouth, which anastomoses with the superior labial. 



