74 ANATOMY OF THE RABBIT 



ing branch from the postauricular branch of the external jugu- 

 lar vein. This anastomosing branch often joins the cephahc 

 vein directly with the external jugular instead of with its 

 postauricular branch. 



The lymphatic system is essentially like that of man, inas- 

 much as the numerous lymph vessels of the superior limb pass 

 through several lymph glands, or nodes, before converging to 

 form a trunk which empties into the thoracic duct near the 

 subclavian vein. However, the axillary and post axillary 

 lymph nodes, and possibly the epicondylar node, will be all 

 of this system the student can find unless he has specially 

 prepared material. 



Since the veins, lymphatics, arteries, and nerves of a region 

 are described separately, the student will be obliged to keep the 

 description of each and the structures which they serve in mind 

 while he is dissecting the arteries and nerves. 



B. ARTERIES OF THE LEFT SHOULDER AND ARM 



(Nos. i-ii, Fig. 23) 



N.B. Before beginning dissection of the arteries, the student 

 must acquire a working knowledge of the veins (A) and the 

 nerves (C) of the shoulder and arm regions, otherwise he will 

 mutilate these structures while dissecting the arteries. 



1. Axillary artery: Subclavian; in the course of the trunk 

 artery which supphes the superior limb, the first rib (Figs. 23, 

 26, I) mark the distal designation of the subclavian a. and the 

 beginning of the axillary artery. Thus the axillary is the con- 

 tinuation of the subclavian and as such is merely that portion 

 of the main trunk which lies in the axilla. 



2. Anterior thoracic (acromio thoracic) a.: Axillary; to 

 proximal ends of the pectorals, subscapular region and possibly 

 to the deltoid mm. (There may be two arteries instead or one 

 or other anomalies.) 



3. Long thoracic a.: Axillary, with thoracicodorsalis (4); to 

 latissimus dorsi and distal ends of pectoral muscles. 



