68 



and the vastus externus. It arises from the sacrum and is 

 attached to the femur. 



The Biceps is a long-, slender muscle arising- from the crest 

 of the ilium just above the acetabulum. It lies in the thigh 

 along- the inner border of the vastus externus and is inserted by 

 a flattened tendinous expansion into the distal end of the 

 femur and the head of the tibia. 



1 GlwTc U.S. 



Fig. 4 

 Fig. 4. Dorsal aspect of the superficial muscles of the left leg of the frog. 



The Semimembranosus is a stout muscle lying along the 

 inner side of the biceps, between it and the rectus intemus minor. 

 It arises from the dorsal angle of the ischial symphysis just 

 beneath the opening of the cloaca and is inserted into the back 

 of the head of the tibia. There is an oblique line of tendinous 

 intersection running obliquely through its middle. 



The Piriformis is a slender muscle which arises from the 

 tip of the urostyle, passes backwards and outwards between 

 the biceps and the semimembranosus and is inserted into the 

 femur at the junction of its proximal and middle thirds. 



265. Ventral Aspect of the Deep Muscles of the 

 Thigh. The Semitendinosus is a long, thin muscle which arises 

 by two heads, an anterior one from the ischium close to the 



