MUSCLES 



OF 



THE HIND-LIMB 



d. Deep muscles of the thigh.\ 



/ 



65 



Lay the frog on its back ("nd dissect /the thigh from the pre- 

 axial swface. Separata the adductor i^gnus aMdlthe rectus 

 intemus major iiMh hlunt iiistruments so^as to expoas the follow- 

 ing muscles : \/ , \ / 



A. The semitMidinosus is a£ long iJiin ihuscle which 



arises,' by\two heads /an antMaoB' one from the 

 ischium clo^ to the fentral angM of the ischial 

 symphysis and the acetabulmn ; /aijd a posterior 

 one from; the\ischj«,l symphysfe. The anterior 

 head passes tnrgtigh a slit/ in tlik adductor 

 magnus and uni|i8s with the posteriOTvhead in 

 the ■ distal third of\the thigh. The tenSop of 

 insertion is long and raun, and joins that of the 

 rectus intemus minor t^ be insei-ted into the 

 tibia just below its head,- 



Divide <^e/ adductor magnus cmd the sartociu^ in the middle 

 and turn th^ cut ends backwards and,' fo^-wards^o as to efcpose 

 the following n^uscles : 



[he adductor brevis is a short wide muscle, lying 



^eneath the upper end of the adductor magnus. 



^arises from the pubic and ischial symphyses, 



anavis inserted into the preaxial surface of the 



proximal half of the femur. 



The pedbb^us is a rather smaller m^uscle, lying 

 along; the outer (extensor) side of the adductor 

 brevis. It aK^ses from the anterior half of the 

 pubic symphysfi^Ln front of the adductor brevis, 

 and is inserted lik^it into the proximal half of 

 the femur. - ' ^ 



The ilio-psoas arises by a "tsdde/ origin from the 

 inner surface of the acetabular poi-tiofi of the 

 ilium : it turns round the anterior border of the 

 ilium, and crosses in front of the hip-joint, where 

 for a short part of its course it is superficial 

 between the heads of the vastus intemus and of 

 the rectus anticus femoris : it then passes down 

 the thigh beneath these muscles, and is inserted 

 into the back of the proximal half of. the femur. 



G 



