VENTRAL CERVICAL MUSCLES 267 
Origin. —The cariniform cartilage of the sternum. 
Insertion —The posterior border of the ramus of the mandible. 
Action— Acting together, to flex the head and neck; acting singly, to incline 
the head and neck to the side of the muscle contracting. 
Structure—The two muscles are fused at their origin, which is fleshy. Near 
| Fic. 266.—ANTERO-LATERAL VIEW OF MUSCLES AND SKELETON OF Horse. 
a, Trapezius; c, brachiocephalicus; d, sterno-cephalicus; f, long head of triceps; 
f’, lateral head of triceps; 
g, anterior superficial pectoral muscle; g’, posterior superficial pectors 
anterior deep pectoral; v, cutaneus colli; 
Z, Supraspinatus; 29, omo-dyoilleus; 39, sterno-thyro-hyoideus; 31, jugular vein; 32, cephalic vein; 
32 1, scapula; 
| 1’, cartilage of scapula; 2, 
aft of humerus; 4’ lateral epicondyle; 5, lateral tuberosity of humerus; 
| 6, deltoid tuberosity; 14, ventral border (‘‘keel"’) of sternum; 14’, cariniform cartilage; 1.R., first rib. (After Ellen- 
berger-Baum, Anat. fiir Kiinstler.) 
ne of scapula; 
the middle of the neck they separate, and, becoming narrower and thinner, each 
muscle passes under the parotid gland and terminates by a flat tendon. The latter 
is connected by a thin aponeurosis with that of the brachiocephalicus. 
Relations—Superficially, the cutaneous muscle; deeply, the sterno-thyro- 
hyoideus and omo-hyoideus muscles. The dorsal edge of the muscle is related to 
the jugular vein, which lies in the jugular furrow. The carotid artery, the vagus, 
