2. =A. thoracica longa= (_p_).--The long thoracic artery is larger than the preceding, leaves the axillary a short distance laterad of it, and passes caudad to the middle portions of the pectoral muscles (8) and continues to the inner surface of the latissimus dorsi. A short distance beyond the long thoracic the axillary divides into two. The more cranial one of these is the =subscapular= (_l_); the other is the =brachial= (_g_′). 3. =A. subscapularis= (_l_).--The subscapular artery passes laterad and gives off a short distance from its origin the =A. thoracicodorsalis= (_t_) and =A. circumflexa humeri posterior= (see below); it may also give rise to the =circumflexa anterior humeri= (_l_′), and to the =profunda brachii= (_u_); these two branches, however, rise more frequently from the brachial artery (_g_′) and are described in connection with it. The subscapular artery then passes through the triangular interval between the scapular end of the long head of the triceps, the latissimus dorsi, and the glenoid border of the scapula. Within this interval it sends muscular branches to the long head of the triceps, the subscapularis, and the latissimus dorsi. That to the latter muscle is very large. At the border of the scapula, opposite the tuberosity of the spine, it turns craniad, passes over the lateral surface of the infraspinatus muscle, supplying it; crosses the spine, and sends branches into the supraspinatus fossa in both directions parallel to the scapular spine. These supply the supraspinatus, acromiotrapezius, and spinotrapezius, and anastomose with the branches of the transversa scapulæ. As the subscapularis turns craniad onto the surface of the infraspinatus it sends dorsad a small branch, the =circumflexa scapulæ=, which passes in the infraspinatus fossa close to its glenoid border as far as the glenovertebral angle, supplying the infraspinatus and latissimus dorsi by lateral branches. [Illustration: FIG. 122.--BLOOD-VESSELS AND THE MORE VENTRAL NERVES OF THE AXILLA, VENTRAL VIEW.