50 LIGAMENTS AND MUSCLES OF THE HORSE. 



Action. — To flex the femur and tense the fascia lata. 



Note. — The fascia lata is a continuation downward of the 

 gluteal fascia, forming a sheath for the muscles of the 

 thigh. It divides into a superficial and a deep layer. The 

 former becomes attached to the patella, the latter passes 

 between the triceps abductor femoris and vastus externus, 

 to be attached to the external border of the femur. 

 *2. Rectus Femoris 



Origin. — By two heads from two depressions in front of the 

 acetabulum. 



Insertion. — To the anterior surface of the patella. 



Action. — To flex the hip joint and extend the stifle. 



3. Vastus Externus. 



Origin. — From the external border and external half of the 



anterior surface of the femur. 

 Insertion. — To the patella. 

 Action. — To extend the stifle. 



4. Vastus Internus. 



Origin. — From the internal border and inner half of the anter- 

 ior surface of the femur. 



Insertion. — To the patella. 



Action. — To extend the stifle. 

 b. Rectus Parvus. 



Origin. — 'From, the ilium, just external to the outer head of tlie 

 rectus femoris. 



Insertio7i. — To the femur just below the head, and to the cap- 

 sular ligament. 



Actio7i. — To tense the capsular ligament during flexion of the 

 femur. 



Note. —No distinct crureus muscle is present in the horse. 



POSTERIOR FEMORAL REGION. 



1. Triceps abductor Jemoris. 



2. Biceps rotator tibialis (Semitendinosiis). 



3. Adductor magnus (^Semimembranosus). 



