746 



CIRCULATORY SYSTEM OF THE DOG 



(4) The inferior cervical artery arises at the first rib, and gives off the ascending 

 cervical and transverse scapular arteries. The former runs on the deep face of the 

 brachiocephalicus, in which it ramifies. The latter goes to the anterior border of 

 the subscapularis, and its largest branch (equivalent to the prescapular of the horse) 

 accompanies the suprascapular nerve. 



(5) The internal thoracic artery is large and sends perforating branches to the 

 pectoral mammary glands. 



The axillary part of the brachial artery gives off the thoraco-acromial and ex- 

 ternal thoracic arteries. 



The thoraco-acromial artery supplies branches to the deltoid and pectoral 

 muscles. 



The external thoracic artery passes backward under cover of the deep pectoral 



Fig. 615. — Superficial Vessels of Head of Dog. 

 1, Facial artery; 3, inferior labial artery; 3, artery of angle of mouth; 4> superior labial artery; 5, lateral nasal 

 artery; 6, dorsal nasal artery; 7, superficial temporal artery; S, transverse facial artery; 9, anterior auricular artery; 

 JO, zygomatico-orbital artery; ii, satellite vein of iO; i^, ant. auricular vein; J5, superficial temporal vein; i^. internal 

 maxillary vein; /.5, post, auricular vein; if?, J 7, external jugular vein; i5, external maxillary vein; J5, ^3, facial vein; 

 j?0, inf. labial vein; ^J , buccinator vein ; ^jS, vena reflexa; j24, superior labial vein ; ;85, vena angularis oculi; ^ff, dorsal 

 nasal vein; a, concha; b, parotid gland; c, mandibular gland; d, mandibular lymph glands; e, mylo-hyoideus; /, 

 digaatricus; g, masseter; h, zygomaticua; i, scutularis; k, temporalis; U orbicularis oculi; m, zygomatic arch; n, re- 

 tractor anguli oris; o, buccinator. (EUenberger-Baum, .\nat. d. Hundes.) 



muscle and ends in the abdominal cutaneous muscle. It sends branches to the 

 mammary glands. 



The common carotid arteries, left and right, arise in that order from the 

 brachiocephalic. In the neck the right one lies on the trachea, the left on the 

 oesophagus. Collateral branches are the posterior thyroid (which may, however, 

 arise from the right or left brachial or the inferior cervical), pharyngeal, anterior 

 thyroid, laryngeal, muscular, tracheal, and glandular (to the mandibular gland). 

 Each carotid divides under the wing of the atlas into occipital and internal and ex- 

 ternal carotid branches. 



The occipital artery is small; it ascends behind the hypoglossal nerve to the 

 paramastoid process, crossing laterally the internal carotid artery land vagus and 

 sympathetic nerves. It curves over the paramastoid process and pursues a flexuous 





