40 



Frederic T. Lewis. 



a small vena comitans for the subclavian artery. Higher up both the 

 subclavian vein and the vena comitans are separated from the artery 

 by the scalenus anterior muscle, and both are dorsal to the sub- 



Vjug. int. V.jy g. e.vt. V.jug. a?ii. 



V.th-dor. 



Fig. 5. Dissection of veins in a man 68 years old. Two-tliirds natural size. 

 y. hr., Venae brachiales ; V. ceph., Y. cephalica ; V. cerv. sui)., Y. cervicalis super- 

 ficialis ; T'. cir. hum. 2>ost., V. circumflexa humeri posterior ; Y. cir. scap., V. 

 circumflexa scapulae; V. jug. ant., Y. jug. ext., Y. jug. int., V. jugularis 

 anterior, externa, interna; T'. mam. int., Y. mammaria interna; Y. prof. 6r., 

 Y. profunda brachii (with a branch, the Y. circumflexa humeri anterior) ; 

 Y. th., Y. thymica; V. th-ac, Y. thoraco-acromialis ; T'. th-dor., \. thoraco- 

 dorsalis; V. th-ep., V. thoraco-epigastrica ; Y. thy. ima, Y. thy. inf., V. 

 thyreoidea ima, inferior; V. tr. colli, Y. transversa colli (from vertebral 

 border of scapula) ; Y. tr. scap., Y. transversa scapulae (from scapular notch) ; 

 V. vert., \. vertebralis. 



clavius muscle, which has been drawn in the figure. Ventral to the 

 subclavius muscle there is a small branch distributed beneath the 

 pectoral muscles ; this branch probably is the principal factor in the 



