VIII.] THE MUSCLES. 301 



posterior part of the sacrum, posterior sacro-sciatic ligament, 

 and coccyx. It is inserted into a rough line below the great 

 trochanter. 



The glutens medius springs from outside the ilium, and is 

 inserted into the great trochanter. 



FIG. 277. HIND VIEW OF THE MUSCLES OF THE PELVIS AND RIGHT THIGH 

 the gluteus maximus and semi-tendinosus being cut and removed. 



i, origin of the gluteus maximus ; i', its insertion ; 2, great sacro-sciatic liga- 

 ment ; 3, gluteus medius ; 4, pyriformis ; 5, tendon of obturator internns ; 6, 

 gemellus inferior (immediately below this, without a number, is the quadratus 

 femoris) ; 7, origin of the semi-tendinosus ; 7', its insertion ; 8, semi-mem- 

 branosus; o, biceps femoris ; 10, adductor ; n, gracilis ; 12, 12, heads of the 

 gastrocnemius ; 13, vastus externus. 



The glutens minimus has a similar origin, but deeper, and 

 a similar insertion. 



The pyriformis arises from the front of the sacrum, and, 

 passing out of the pelvis by the sacro-sciatic notch, is inserted 

 into the great trochanter. 



