MUSCULAR SYSTEM. 157 



hock; in front of which it is continuous with the tendinous va- 

 ginae, formed for the passage of the extensor tendons : on the 

 outer side this faschia sends a broad process inward, between 

 the extensor pedis and peroneus, which is fixed to the body of 

 the tibia, inclosing the latter muscle in a complete sheath. Be- 

 yond this, the anterior faschia becomes continuous with the 

 posterior. 



The chief attachments of the posterior division of the faschia 

 are, the condyles, and postero-inferior part of the body of the 

 femoral bone ; the postero-lateral parts of both extremities of 

 the tibia, and the entire inner side of its body ; the lateral liga- 

 ments of the hock ; and the tendinous point of the os calcis. 



1.— ANTERIOR FEMORO-CRURAL REGION. 



Of the muscles situated in this region, two are extensors of the 

 leg and foot, and at the same time aiders in the flexion of the 

 hock : the other is a direct flexor of the hock. They are all three 

 bound down to the tibia by a strong tendinous faschia. 



EXTENSOR PEDIS. — Femoro-prepha/dfigeus. 



Situation. — Superficial ; anterior part of the leg. 



Fonn. — Elongated ; fusiform : flattened from before back- 

 wards. 



Attachment. — Superiorly, to a roughened depression upon 

 the antero-inferior part of the external condyle of the femoral 

 bone. Inferiorly, to the coronal process of the os pedis, and to the 

 superior edge of the bone in the interval between the lateral 

 cartilages. 



Relations. — Anteriorly, with the faschia and skin, and the 

 aponeurotic tendon of the biceps ; postero-externally, with the 

 peroneus; postero-internally, with the flexor metacarpi ; poste- 

 ro-superiorly, with the capsular ligament of the stifle joint, the 

 tendon passing through a groove upon the front of the tibia. 



Structure. — The muscle commences, superiorly, by a small flat 

 tendon, which is common to it and the flexor metatarsi. Upon 

 the tibia it becomes fleshy, exhibiting two or three thin tendi- 

 nous intersections, together with aponeurotic surfaces. A little 

 above the hock the fleshy belly ends in a flat tendon, which takes 

 its course in front of the hock through a theca prepared for it, 

 and upon the cannon (about one-third of its length downward) 

 enters into union with the tendon of the peroneus, and so inti- 

 mately that the two tendons appear but as one until they have 

 descended as low as the fetlock joint, over which they disunite 

 and again run separate. As it passes the front of this joint, the 



