354 ANATOMICAL TECHNOLOGY. 



(B) A. profunda superior (Fig. 105). This arises opposite the musculo-spiral nerve 

 (Fig. 105) and follows its course. 



(C) A. nutriens. In Fig. 105 it is the vessel passing between the A. and the br. It is 

 represented too large. It passes to the bone, and entering the nutrient foramen, is distrib- 

 uted to the shaft of the humerus. 



(D) A. anastomotica magna (Fig. 105, between the abbreviations hmr. and trc., near 

 the distal end of the humerus). This artery passes to the convexity of the elbow. 



Upon reaching the foramen epitrochleare, the A. brachialis traverses it in company 

 with the median nerve (Fig. 102, 105) and reaches the concavity of the elbow. 



944. A. radialis (Fig. 102, 105). The brachial artery distad 

 of the concavity of the elbow is continued as the radial. It passes 

 caudad of the tendon of the biceps muscle and en tad of the prona- 

 tor teres (Fig. 105, 701). About opposite the middle of the ante- 

 brachium the radial artery is covered only by skin and fascia. At 

 this point the artery divides into two unequal branches ; the smaller 

 or ventral one follows the radial nerve, while the principal one in- 

 clines dorsad, and just distad of the styloid process of the radius it 

 curves around to the dorsal side of the manus. 



To expose the artery, divide the M. pronator teres about 2 cm. 

 from its origin and turn the two ends aside, and divide longitudi- 

 nally the antebrachial fascia along its ventral aspect. 



The radial artery gives rise to several muscular branches that 

 are unnamed and to the following named branches : 



(A) A. radialis recurrens. This arises in the concavity of the elbow on the caudal 

 side of the tendon of the biceps (Fig. 105). It is distributed to the various structures in 

 the concavity of the elbow. 



(B) A. ulnaris recurrens (Fig. 105). This is shown in the figure as arising from the 

 radial opposite the point where it crosses the M. biceps. It extends proximad to the struc- 

 tures at the convexity of the elbow. It is called ulnar recurrens on account of its distri- 

 bution. See Quain, A, I, 408, and Gray, A, 520. 



(C) A. interosseus posterior. This artery arises from the ental aspect of the radial 

 just distad of the tendon of the biceps. It extends nearly directly dorsad, and may be 

 demonstrated by tearing away the muscles surrounding it. 



(D) A. interosseus anterior (Fig. 105, A. interosseus). This artery arises, either sep- 

 arately or as a common trunk with the ulnar, from the ental aspect of the radial about 

 3 cm. from the Fm. epitrochkare. It passes distad along the antebrachium on the ventral 

 side of the interosseus ligament. It may easily be followed by turning the radial artery 

 slightly aside and then separating the muscles with the tracer. 



945. A. ulnaris (Fig. 102 and 105). In man the ulnar artery 

 is about equal in size to the radial, and the division of the brachial 

 to form them is very near the elbow or even in the brachium (Quain, 

 A, I, 403) ; but in the cat the ulnar is so small that it is sometimes 

 not injected at all with plaster. In its course and distribution it cor- 



