236 MYOLOGY. 



Origin. — From the shaft of the ischium on either side of the 

 conjoined tendon of the pyriformis and -obturator internus, their 

 fibres blending with it and passing outwards. There may be 

 another flat and somewhat large muscle situated between the 

 above and the obturator externus, originating also from the ischial 

 ramus. 



Insertion. — In the trochanteric fossa. 



Relation. — Posteriorly with the sciatic nerves ; anteriorly 

 with the capsular ligament of the hip joint, and the obturator 

 externus. 



Action. — Like the preceding, to rotate the femur outwards. 



Femoral Eegion. 



The muscles of this region cover more or less the shaft of the 

 femur, some of them reaching as far as, or below the stifle joint ; 

 the majority of them have a pelvic origin. These muscles may 

 be conveniently divided into the four following groups : — 



Internal. | Anterior. 



External. I Posterior. 



Internal Femoral Group. 



adductors. 



These form the large fleshy mass situated between the inferior 

 pelvic surface and the stifle joint ; they are six in number : — 



Sartorius. 



Gracilis. 



Pectineus. 



Adductor brevis. \ 



Adductor longns. '- Triceps adductor femoris. 



Adductor ma^nus. ) 



SARTORIUS. 



{Suhlumho-tihialis. ) 



(Fig. 77. h.) 



Situated in the abdominal cavity at the pelvic inlet, and along 

 the inner aspect of the thigh, it is long, thin, fleshy, and pyra- 

 midal, extending obliquely downwards, forwards, and outwards. 



