70 



THE ANATOMY OF THE HORSE. 



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



The Vastus Exteenus (Plate 18) arises from the outer surface of 

 the femur, and from the outer half of the anterior surface of the same 

 bone. Its fibres become inserted along with the rectus femoris into the 

 patella. 



Action. — To extend the stifle. 



The Rectus Pakvus (Fig. 2) is very slender when compared with the 

 muscles between which it is placed, being about the thickness of a human 

 finger. It arises from the ilium, external to the pit from which the 

 outer head of the rectus femoris takes origin. Passing in front of the 





"\^ji 



Fig. 2. 



Muscles of the Tail, deep Muscles of the Hip, and Pelvic Ligaments {Cliauveau.) 



1. Erector coccygis ; 2. Curvator coccygia ; 3. Depressor coccygis ; 4. Compressor ooccygis ; 

 5. Deep gluteus ; 6. Rectus parvus ; 7. Common tendon of obturator interniis and pyriformis ; 

 S. Gemelli ; 9. Accessory fasciculus of the same ; 10. Quadratus femoris ; 11. Sacro-sciatic ligament ; 

 12. Great sacro-sciatic foramen ; 13. Superior ilio-sacral ligament ; 14. Inferior ilio-sacral ligament. 



capsular ligament of the hip-joint, to which it adheres, it insinuates 

 itself between the two vasti muscles, and is inserted into the anterior 

 surface of the femur. 



Action. — The muscle is of too slender a size to exert any appreci- 

 able flexor action on the hip-joint, and probably its function is to raise 

 the capsular ligament during flexion of the joint. {See footnote, 

 page 63.) 



Directions. — The dissector is now in a position to detach the limb 

 from the trunk, and this should be done by cutting through the bone 

 and soft structures, below the level of the internal trochanter. It is 

 necessary to make the section at this point, in order to leave the hip- 



