26 BODY. 



dia'lis, down by outer side of radial artery, just concealed by 

 supinator longus till within 3 inches of wrist, where pierces 

 deep fascia of outer side forearm j divides to supply radial 

 side of ball of thumb, (communicating with external cutaneous 

 nerve), and on back of hand forms an arch with ulnar, giving 

 off 4 digital nerves J the ist to ulnar side of thumb j the ad to 

 radial side of index ; the 3d, adjoining sides of index and mid- 

 dle; the 4th, adjoining sides of middle and ring fingers. 

 Interos'seus posterior, pierces supinator brevis, winding to 

 back of forearm, passing down to wrist, there having gangli- 

 onic enlargement. Supplies carpus, and all muscles on back 

 of forearm except anconeus, supinator longus and extensor 

 carpi radialis longior. 



o . 



BOD Y. 



MUSCLES. 



(l) BACK, FIRST LAYER, 2. 



Trape'ziUS! inner 3d superior curved occipital line, liga- 

 mentum nuchse, spinous processes of jth cervical and all the 

 dorsal vertebrae posterior border clavicle, superior margin 

 acromian process and superior border spine of scapula. [Spi- 

 nal accessory, cervical plexus.] 



Latis'iiULUS dor'si: aponeurosis from spinal processes 6 lower 

 dorsal, all lumbar and sacral vertebrae, external lip iliac crest 

 twisting upon itself so as to be inserted into bicipital groove 

 ofhumerus. [Subscapular.] 



(2) BACK, SECOND LAYER, 3. 



Leva'tor an'guli SCap'vtla : transverse processes of 3 or 4 supe- 

 rior cervical vertebrae posterior border scapula, [sth cervi- 

 cal, cervical plexus.] 



Ehomboide'US mi'nor : ligamentum nucha?, spinal processes jth 

 cervical and ist dorsal vertebras down- and outwards to root 

 scapular spine. [$th cervical.] 



Bhomboide'uS ma'jor : spinal processes superior dorsal vete- 

 bras tendinous arch along vertebral border scapula. [5th 

 cervical.] 



(3) BACK, THIRD LAYER, 4. 



Serra'tttS pOSti'CUS SUpe'rior: ligamentum nuchae, spinal proces- 

 ses jth cervical and 2 or 3 superior dorsal vertebrae superior 

 border ad, 3d, 4th, 5th ribs. [Posterior external brs. cervical.] 



Serra'tus pOSti'CUS infe'rior : spinal processes nth and i2th dor- 

 sal, ist, 2d and 3d lumbar vertebras up and out to inferio 

 border 4 inferior ribs. [External branches dorsal.] 



