96 THE MUSCLES. 



an aponeurosis, which covers the other two muscular masses and 

 combines with their tendons. 



112. [b.] M. vastus externus (Fig. 80 v.e.). 



It arises from the upper and hinder extremity of the iliac bone 

 (Fig". 43 W) behind the glittaeus, which here sinks in between this 

 muscle and the rectus anterior. 



113. [c] M. vastus interims (Figs. 81, 82 ri). 



It arises from the whole of the under and outer surfaces of the 

 hip-joint capsule, and from tendinous slips which pass from this 

 capsule downwards on the under surface of the muscle, (from the 

 pubis and the femur I have not seen any fibres of origin, as stated 

 by others). Anteriorly the vastus may easily be separated into two 

 heads. The two vasti unite and form one muscular belly, in the 

 formation of which, as above stated, the rectus anticus takes no 

 part. This united muscle passes into a tendon which, without the 

 mediation of a patella, passes over the knee-joint to be inserted into 

 the anterior extremity of the tibio fibula, and is prolonged into the 

 fascia of the leg. 



114. M. iUo-fihularis s. lAceps (Fig. 80 h). 



Dugès, ilio-péronien, n. 149. — Zenker, flexor externus tibiae, p. 42. 



This is a long-, somewhat narrow muscle, which lies to the inner 

 side of, and partly covered by, the vastus externus, between which 

 and the semimembranous it is placed. It arises by a tendon between 

 the ilio-psoas and piriformis from the ilium above the acetabulum 

 and behind the origin of the vastus externus. From here it passes 

 backwards, separated from the vasttis externus by a strong ligam. 

 interinusculare. On the inner side of this muscle, between it and 

 the m. semimembranosus, nui the vessels of the thigh and the N. 

 ischiadicus. The muscle then divides into two portions, of which 

 one is inserted high up on the inner and under surface of the 

 femur. This is probably the muscle which Klein {J. c, p. 61) 

 describes as the extensor brevis. The other long muscular belly 

 passes into a thin tendon, opposite the hinder extremity of the 

 thigh, it divides into two portions ; the anterior is inserted into 

 the dorsal surface of the hinder extremity of the femur, the other 

 into the dorsal surface of the tibio-fibula. Between the two is 

 stretched an arch with the concavity outwards. This insertion of 

 the biceps is covered by the stronger tendon of origin of the vi. gas- 

 trocnemius (compare Fig. 87). 



