THE EXTERNAL CAROTID ARTERY 645 



upward under cover of the parotid gland, to which it gives branches, and divides 

 into several branches which supply the skin and muscles of the external ear (Fig. 

 560). The posterior branch passes to the posterior part of the base of the ear, 

 where it divides into two branches; of these, one (Ramus intermedins) passes up the 

 convex surface of the external ear to the apex, while the other (Ramus medialis) 

 winds around to the anterior (medial) border, and forms an arch with the inter- 



Fig, 562. — Deep Dissection of Head of Horse. 

 The left ramus of the mandible and structures connected with it have been removed, a, a, Stumps of styloglossus; 

 b, genio-glossus ; c, genio-hyoideus; d, omo-hyoideus; e, kerato-hyoideus; /, thyro-hyoideus; g, thyro-pharyngeus ; 

 h, crico-thyroideus ; i, sterno-thyroideus; k, thyroid gland; m, crico-pharyngeus; n, palatinus and palato-pharyngeufs; 

 o, pterygoideus lateraUs; p, tensor palati; q, levator palati; r, temporalis; s, rectus cap. ventralis major; t, obliquus 

 cap. ant.; u, guttural pouch; v, great cornu of hyoid bone, extremity of which is removed and indicated by dotted line; 

 w, position of small cornu, dotted line ; x, thyroid cornu; y, tongue; ^, anterior pillar of soft palate; .?, superficial tem- 

 poral nerve; 2, chorda tympani; S, stump of inferior alveolar nerve; 4< 4< lingual nerve, intermediate part removed; S, 

 deep temporal nerve; 6, masseteric nerve; 7, buccinator nerve; 5, great palatine nerve; 9, infraorbital nerve; 10, 

 sphenopalatine and posterior nasal nerves; 11, spinal accessory nerve; 1£, vagus; 13, pharyngeal branch of vagus; 

 14, anterior laryngeal nerve; IS, vago-sympathetic trunk; 16, sympathetic, with anterior cervical ganghon a little fur- 

 ther back; 17, glosso-pharjmgeal nerve; 18, pharyngeal and 19, hngual, branches of glosso-pharyngeal ; SO, hj-poglossal 

 nerve; ;^^, left recurrent nerve; ^5, common carotid artery; ^5, parotid branch; ^-4, anterior thyroid or thyro-laryngeal 

 artery; 24', laryngeal artery; £5, occipital artery; £6, internal carotid artery; £7, external carotid artery; £8,30, ex- 

 ternal maxillary artery; ;?5, pharyngeal artery; Si, lingual artery; S^, internal maxillary artery; S^, stump of inferior 

 alveolar artery; 34, middle meningeal artery; 35, deep temporal artery; 36, buccinator artery; 37, palatine artery; 

 S8, end of internal maxillary artery; 39, right external maxillary artery; 40, satellite vein of 39; 4i, right parotid duct; 

 42, mandibular lymph glands; 43, parapharyngeal lymph glands; 44, trachea; 45, wing of atlas; 4^, dotted line indi- 

 cating outline of mandibular gland; ^7, lacrimal gland. (After Ellenberger-Baum, Top. Anat. d. Pferdes.) 



mediate branch. The lateral branch (Ramus lateralis) passes up the posterior 

 (lateral) border of the ear and forms an arch with the intermediate branch. The 

 deep branch (A. auricularis profunda) enters the interval between the external 

 acoustic process and mastoid process, and passes through an opening into the 

 interior of the external ear and ramifies in the skin which lines it. It gives off the 

 stylomastoid artery, which passes through the stylomastoid foramen into the tym- 



