ANTERIOR FEMORAL REGION. 243 



V A STL'S EXTERXUS. 



(Femoro-rotuleus Externus. ) 

 (PL. III. 35.) 



Situated on the outer side of the rectus femoris, this muscle 

 is broad, thick, flattened laterally, and semi-ovoid, extending 

 downwards and forwards ; it is fleshy, with strong tendinous 

 intersections. 



Origin. From the external and part of the anterior aspects 

 of the shaft of the femur, and from the base of the trochanter 

 major downwards. 



Insertion, To the upper and outer part of the patella ; or 

 it may join the rectus femoris. 



Relation. Externally with the tensor fascie latse, and gluteus 

 externus; internally with the rectus, crureus, and vastus internus, 

 with which inferiorly it is intimately blended ; posteriorly with 

 the triceps abductor femoris and the femur. 



Action. To extend the leg. 



VASTUS IXTERNUS. 



(Femoro-rotuleus Internus.} 



(Fie. 76. k.) 



Corresponding to the externus, this muscle is situated on the 

 inner side of the rectus femoris, the two forming a channel in 

 which are lodged the rectus and crureus. It is semi-ovoid, and 

 fleshy, becoming tendinous at its insertion. 



Origin. From the neck of the femur, its antero-internal 

 surface, and the trochanter internus. 



Insertion. To the upper and inner side of the patella. 



Relation. Externally with the rectus ; internally with the 

 sartorius, pectineus, psoas magnus, iliacus, adductor magnus, and 

 crural fascia. 



Action. To extend the leg. 



CRUREUS. 

 (Femoro-rotuleus Medius.) 



Situated below the rectus, and between the two vasti, this 

 muscle is small, cylindrical, fleshy, and tendinous at its extremi- 

 ties ; it is separated from the vasti with difficulty. 



