298 



THE SPINAL NERVES. 



ramifies in the integument of the lower two-thirds, extending as far as or somewhat 

 beyond the wrist. It communicates with a branch of the radial nerve, and with 

 the lower external cutaneous branch of the musculo-spiral nerve. 



Varieties. The musculo-cutaneous nerve proper occasionally receives fibres from the 

 seventh cervical nerve. 



In some cases the constituent fibres of the nerve remain adherent to the outer head and 



10 



Fig. 198. DEEP VIEW OF THE ANTERIOR NERVES OF THE SHOULDER AND ARM. 



Hirschfeld and Leveille.) | 



(From Sappey, after 



1, musculo-cutaneous nerve, giving off 2, the branch to the coraco-brachialis muscle ; 3, branch to 

 the biceps, represented incorrectly as given off before the nerve pierces the coraco-brachialis ; 4, branch 

 to brachialis anticus ; 5, communicating branch from the median to the musculo-cutaneous nerve (an 

 infrequent variety) ; 6, continuation of the nerve to its cutaneous distribution ; 7, musculo-spiral nerve 

 in the interval between the brachialis anticus and supinator longus muscles ; 8, inferior external 

 cutaneous branch of the musculo-spiral ; 9, the large and small internal cutaneous nerves divided ; 10, 

 anterior branch of the internal cutaneous 11, median nerve; to the inner side of this the ulnar nerve 

 is crossed by the line from 11. 



Fig. 199. DEEP VIEW OF THE ANTERIOR NERVES OF THE FOREARM AND HAND. 



Hirschfeld and Leveille.) | 



(From Sappev, after 



12, median nerve ; 13, its branch to the pronator teres ; 14, branch to the superficial fle>or muscles, 

 which have been removed ; 15, branch to the flexor profundus digitorum ; 16, branch to the flexor 

 longus pollicis ; 17, anterior interosseous nerve ; 18, palmar cutaneous branch cut short ; 19, branch to 

 short muscles of thumb ; 20, 21, digital branches to thumb ; 22, 23, 24, third, fourth, and fifth 

 digital branches ; 25, branch given by ulnar nerve to flexor carpi ulnaris ; 26, branch to flexor profundus 

 digitorum ; 27, cutaneous twig ; 28, dorsal branch of .ulnar ; 29, superficial palmar portion ; 30, 31, 

 digital branches to ring and little fingers ; 32, deep palmar branch ; 33, its branch to short muscles of 

 little finger ; 34, 35, 36, twigs given by deep branch of ulnar to third and fourth lumbricales, all the 

 interosseous muscles, and the adductors of the thumb. 



