350 SHOULDER-GIRDLE IN MONOTREMES, 



The sixth nerve splits into two divisions, the dorsal one of wliich 

 (53) joins the dorsal cord formed by the iv. and v. nerves ; and 

 the result is a stout trunk which gives off the following numerous 

 branches : — 



32. 32a. Nn. to subscapularis. 

 35. N. to teres major. 



31. N. to teies minor. 



27. N. axillaris, 



28. N. to clavicular deltoid. 



29. N. to scapular deltoid. 



30. Twig to infraspinatus. 



33. Cutaneous branches to arm. 



34. N. radialis superficialis to forearm (extensor surface). 



Just before this dorsal portion of the sixth joins the cord from 

 the iv. and v. nerves, it gives out two branches ; one of these 

 merely runs to the seventh nerve, the other (38) passes posteriorly 

 and gives off three branches, one (38a) to the scai)ular part of the 

 latissinius ; the second (39) to the anterior dorsal part of the 

 latissimus ; while the third goes to join a branch (39b) from the 

 seventh nerve to supply the anterior dorsal part of the latissimus 

 (39a), and the posterior dorsal part of the same raiiscle (40). 



N. cervicalis vii. This nerve divides into two cords. The 

 anterior one of them, after receiving the communication from the 

 dorsal part of the vi., divides into two parts. One of the latter 

 is now joined by the venti'al division of the vi. nerve, and the 

 resulting cord is joined by the ventral division formed by the 

 junction of the iv. and v. nerves. As a result, we have a stout 

 cord which gives off the following branches :— 



50. N. to epicoraco-bi-achialis. 



36. N. to pectoralis major, which gives off in turn 



