MUSCLES OF THE ANTERIOR LIMBS. 



Fig. 188. 

 B C. 



337 



MUSCLES OF THE FOREARM AND PAW OF THE DOG. 



i. Anterior superficial region.— 1, Short flexor of the forearm (iinterior brachial) ; 2, long flexor of 

 the forearm (brachial biceps) ; 3, anconeus ; 4, round pronator ; 5, anterior extensor of the 

 metacarpus (external radial) ; 6, its tendon of insertion, destined for the lourth metacarpal l.one ; 



7, that which goes to the third ; 8, external oblique of the metacarpus (long abductor and short 

 extensor of the thumb); 9, common extensor of the digits; 9', its terminal tendon at the point 

 where it divides into four branches ; 10, proper extensor of the three external digits, or lateral 

 extensor of the phalanges in the horse ; 10', its terminal tendon at the commencement of its 

 trifurcation ; 11, proper extensor of the thumb and index; 11', its terminal tendon; 12, 12, long 

 supinator ; 13, external flexor of the metacarpus (posterior ulnar). 



B. Deep anterior region.— I, Round pronator ; 2, short supinator ; 3, proper extensor of the thumb 

 and index ; 4, oblique extensor of the metacarpus ; 5, superior insertion of the anterior extensor 

 of the metacarpus ; 6, ditto of the anterior extensor of the phalanges ; 7, proper extensor of the 

 three external digits; 8, internal flexor of the metacarpus (great palmar); 9, levator humeri; 

 10, 11, long and short flexors of the forearm. 



C. Deep posterior region. — 1, Round pronator ; 2, square pronator ; 3, ulnar portion of the perforans ; 



4, radial portion of the same (long flexor of the thumb) ; 5, terminal tendon of the same; 6, 

 tendon of the small palmar (division of the perforans) ; 7, anterior extensor of the metacarpus ; 



8, long supinator ; 9, epicondyloid insertion of the perforatus, perforans, and oblique and internal 

 flexors of the metacarpus; 10, olecranian insertion of the oblique flexor; 11, supercarpal inser- 

 tion of the same; 12, terminal tendon of the internal flexor ; 13, proper extensor of the external 

 digits ; 14, coraco-radialis ; 15, tendon of the extensors of the forearm. 



D. Superficial posterior region, and the special muscles of the foot or hand. — 1, Perforatus; 1', its 

 tendon divided at its passage behind the carpal sheath; 2. ditto, its terminal branches; 3, per- 

 forans ; 3', its tendon divided after its exit from the carpal sheath ; 4, ditto, its terminal branches ; 



5, tendon of the internal flexor of the metacarpus ; 6, oblique flexor (anterior ulnar) ; 7, inferior 

 extremity of the long supinator; 8, terminal tendon of the oblique extensor of the metacarpus; 



9, short abductor of the thumb; 10, opponent of the thumb; 11, short flexor of the thumb; 

 12, adductor of the thumb, transformed, in the dos, into the adductor of the index ; 13, short 

 flexor of the small digit; 14. adductor of the small digit; 15, opponent of the small digit; 

 16, 16 metacarpal interosseous muscles, a, a, a. Bands which maintain the flexor tendons on 

 the metacarpo-phalangean articulations, and limit the separation of the digits; collectively, they 

 represent, in a rudimentary state, the palmar aponeurosis of Man. 



