The distribution of the nerves of the brachial plexus is as follows (Fig. 31): (a) supracoracoideus to the muscle of that name and to the integument of the breast; (b) thoraci inferiores nerves (10a)--a complex of nerves from the eighth, ninth, and tenth spinal stems--lead to the costo-coracoideus muscles and to the anterior part of the transversus abdominis muscle; (c) the pectoralis (19), a large nerve leading to the muscle of that name; (d) cutaneus pectoralis (18), fine branches from the XIth spinal nerve to the integument of the axilla and the neighboring parts of the breast; (e) coraco-brachialis (22) to the like named muscle; (f) cutaneus brachii et antebrachii medialis (25 + 42) to the medial side of the integument of the upper and fore arm; (g) brachialis longus inferior (21), a large nerve that supplies the biceps and humero-antebrachialis inferior muscles, and then divides into the medianus and ulnaris inferior nerves; (h) subscapularis (29) to the like named muscle; (i) scapulo-humeralis profundus (36a) to the like named muscle; (j) axillaris, a large stem that divides into two main twigs that lead to the skin of the lateral side of the upper arm, to the proximal part of the forearm, to the humero-radialis muscle, and to the deltoides coraco-sternalis muscle; (k) dorsalis scapulæ (posterior) (31) to the deltoideus scapularis muscle; (1) teres major (29b), one (alligator) or two (crocodile) middle-sized nerves to the teres major muscle; (m) latissimi dorsi (29b) to the like named muscle; (n) brachialis longus superior (radialis) (not shown in Figure 31) to the extensor side of forearm and the hand. Of the spinal nerves between the brachial and crural plexuses Bronn gives no description for the Crocodilia. The most posterior nerve of the former plexus is the eleventh and the most anterior nerve to take part in the latter is the twenty-third, so that there are eleven nerves that are doubtless distributed to the regions not supplied by the two plexuses. [Illustration: FIG. 32. CRURAL PLEXUS AND ISCHIADIC PLEXUS OF THE LEFT SIDE OF A. MISSISSIPPIENSIS. THE NERVE BRANCHES ARE SHOWN AS FAR AS THEIR ENTRANCE INTO THE MUSCLES. THE CRURAL PLEXUS IS MADE UP OF THE PRESACRAL STEMS _a_, _b_, _c_. THE OBTURATOR NERVE IS BUILT OF TWO BRANCHES FROM STEMS A & B. (FROM BRONN, AFTER GADOW.) _a_, _b_, _c_. presacral nerves. _α_ & _β_. postsacral nerves. _s_ = _XXVI_. sacral nerve (26th spinal nerve). 2. to extensor ileo-tibialis muscle. 3. to femoro-tibialis muscle. 4. to ileo-fibularis muscle. 5. to ileo-femoralis muscle. 6. to caudi-ileo-femoralis muscle. 7. caudi-femoralis muscle. 8. to flexor tibialis externus muscle. 9. to flexor tibialis internus muscle. 11. to ischio-femoralis muscle. 13. pubo-ischio-femoralis internus. 14. pubo-ischio-femoralis externus muscle. 15. to pubo-ischio-femoralis posterior muscle.]