MUSCLES OF Till: A\Ti:i;ioli LIMBS. -'<::, 



of tli os pedis, and tho median imprints situated behind this crest, 

 in Incoming confounded at its sides with tho tissue of tho lateral fibro- 

 cartilages. 



Tho navicular sheath is vesicular in form ; it covers tho navicular bone 

 mid tho single ligament of tho podal articulation, becomes reflected on tho 

 plantar aponeurosis in front of this ligament, and ascends to the inferior 

 cnlilc-sac of tho sesamoid sheath, where it is again reflected and continued 

 by itself. It therefore forms two mls-de-sac, one superior, the other inferior, 

 which arc readily perceived in a longitudinal and vertical section of tho 

 digital region. The first is in contact with the posterior cul-de-sac of the 

 syuovial membrane of the pedal articulation, and is separated from the 

 inferior sue of tho sesamoid sheath by a transverse layer of yellow fibrous 

 tissue which attaches tho perforans tendon to tho posterior face of the second 

 phalanx. The second is situated beneath the interosseous ligament which 

 unites tho navicular bone to tho third phalanx. 



Tho reinforcing sheath of tho perforans tendon is formed by a fibrous 

 membrane applied against the posterior face of the plantar aponeurosis. 

 This membrane adheres intimately below, to the expansion it covers, and 

 ends in becoming entirely confounded with it. It is fixed, at its borders, to 

 the inferior extremity of the first phalanx, by means of two lateral bands. 



/.'' lotions. The epitrochleaii muscular portion is covered, at its origin, 

 by the external cul-de-sac of the elbow joint, which sac also covers the other 

 muscles attached to the epitrochlea the external and oblique flexors of the 

 metacarpus. It responds, anteriorly, with the radius and radial portion of 

 the muscle ; posteriorly, with tho perforatus ; externally, with the external 

 flexor of the metacarpus; inwardly, with the internal and oblique flexors 

 of the same ray. 



The ulnar portion, covered by the antibrachial aponeurosis, covers the 

 epitrochleau portion. 



Tho radial division is comprised between the latter and the posterior face 

 of tho radius. 



Tho tendon is in contact, posteriorly, with that of the perforatus ; 

 anteriorly, with tho posterior ligament of tho carpus, the suspensory ligament 

 of the fetlock, and the sesamoid groove ; by its sides, with tho vessels and 

 nerves of the digit. Its terminal expansion is covered by the plantar cushion, 

 which adheres to it, in front, in the most intimate manner ; it covers tho 

 navicular bon--. 



Action. This muscle flexes tho phalanges on one another and on tho 

 arpus. It also concurs in the flexion of tho entire foot on tho fore-arm. 

 The band which attaches its tendon In-hind the carpus, as well as its phahm- 

 geal reinforcing sheath, gives it tho mechanical power necessary to support 

 tho angle of tho motacarpo-phalangeal articulation and tho digital region, 

 while tin.- animal is in a standing posturo. 



i In the "Deep Flexor," of M. Chauveau's description, wo find included 

 two portions which are separately named and described by Mr. Porcivall 

 and Professor (iiirlt. These arothe ulnaris acceworitw and raaiaKl accfaoriiu 

 of the t'i n-iner, and the cubito-ulnar and radial brain-he* of tho latter. These, 

 in reality, are jxirtions of the perforans, and have boon R" ;--d in this 



tnatise. Though arising independently, they terminate in tho performs 

 ten-Ion before it leaves tho carpal sheath, and join with it in flexing tho 

 metacarpus and phalanges.) 



