MUSCLES OF THE ANTERIOR LIMBS. 335 



furnishes a fasciculus to tl,e perforans, after which it enters the carpal sheath with the latter, 

 ami terminates on the great internal digit. 



The perforans presents an epitrochlean portion, divided into two fasciculi, between which 

 is interposed the perforatus— an ulnar portion very like that of the Horse, but inserted to 

 tlie inner side of the olecranon ; and an extremely rudimentary radial portion. These three 

 portions unite into a common tendon which, on reaching the middle of the metacarpus, quadri- 

 furcates to give a branch to each of the digits ; the two branches for the small digits pass 

 beneath a band which, from the sesamoid bones, is carried to the inner side of the second 

 plialanx, and takes the place of the ring of the perforatus. 



Co Camivora.— In the Dog and Cat, the anttrior extensor of the metacarpus divides, at 



Fig. 187. 



ANTERIOR ANTIBRACHIAL REGION OF THE PIG (EXTERNAL AND INTERNAL FACES). 



1, Anterior extensor of the metacarpus ; 2, oblique extensor of the metacarpus ; 3, proper extensor 

 of the great internal digit ; 3', its tendon, which gives off a thin branch to the small internal 

 digit; 4, proper extensor of the great external digit; 4', its tendon; 5, common extensor of the 

 two internal digits; 5', its tendon before bifurcation; 6, common extensor of the two external 

 digits ; 6', its tendon before bifurcation ; 7, proper extensor of the small external digit (lateral 

 extensor of the phalanges) ; 7', its tendon. 



its lower extremity, into two branches, which exactly resemble those of the terminal tendons of 

 the two external radial muscles of Man : one is inserted into the metacarpus of the index, the 

 other into the metacarpus of the medius (Fig. 188, a, 5, 6, 7). 



The oblique extejisor passes to the metacarpus of the thumb ; it furnishes, besides, a small 

 particular branch that glides, by means of a sesamoid, over the third bone of the inferior row 

 of the carpus, and is blended with the posterior ligament of the carpus (Fig. 188, a, 8 ; B, 4 ; 

 D, 8); it separates the thumb from the other digits, but we think it scarcely adapted for the 

 function of extensor. 



The anterior extensor of the phalanges of Solipeds is replaced by a single muscle, the com- 

 mon extensor of the digits, terminated by a quadrifurcated tendon, whose branches are distributed 

 to the four great digits (Fig. 188, a, 9, 9'). 



The tendon of the lateral extensor is divided into three branches, which are inserted on the 

 anterior face of the three outer digits, and are blended with the tendons of the common 



