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IO8 ANATOMY OF THE DOMESTIC FOWL 



Relations. Superiorly, the extensor indicis longus, and inferiorly, 

 the ulna. 



Action. A flexor of the forearm. 



Extensor Indicis Longus (Fig. 13, No. 22; Fig. 15, No. 13). Lo- 

 cation. Infero-lateral to the radius. 



Origin. From about one-half the surface of the proximal portion 

 of the radius. 



Insertion. Possesses a long tendon which passing over a groove at 

 the distal end of the ulna and receiving muscular fibers at the base 

 of the metacarpus, extends down the anterior part of the hand 

 and is inclosed in a sheath in front of the superior part of the first 

 phalanx of the index-finger. This tendon is inserted into the an- 

 terior upper rim of the distal phalanx. 



Shape. Small, thin. 



Relations. Supero-laterally with the radius. 



Action. Extensor of the digit. 



Flexor Digitorum Sublimis. Location. The forearm. 



Origin. From the internal condyle of the humerus. 



Insertion. Passing over the wrist, it is inserted to the middle 

 phalanx of the hand. 



Shape. A musculo-tendinous band, "rather delicate and rudi- 

 mentary. 



Relations. Closely adhering to the integument that stretches from 

 the internal condyle of the humerus to the wrist. 



Action. Assists these muscles. A flexor. 



Flexor Digitorum Profundus (Fig. 13, No. 21). Location 

 Lateral side of the ulna. 



Origin. By two heads from the proximal extremity of the ulna, 

 between which the brachialis anticus passes. 



Insertion. The two bellies uniting are attached to the under 

 side of the shaft of the ulna. It becomes tendinous about the middle 

 of the shaft, and inserts to the ulnar side of the base of the distal 

 joint of the index-finger. 



Shape. A fleshy belly with long tendon. 



Relations. Inferiorly, with the flexor carpi ulnaris, superiorly, 

 with the pronator brevis. 



Action. A flexor of the digit. 



Flexor Carpi Ulnaris (Fig. 13, No. 19). Location. Inferior part 

 of the forearm. 



Origin. By two strong tendons; one from the side and posterior 



