FEOG 225 



IV. Muscles of the hind lirrib. 



Straighten the hiad leg to its fullest extent, lay 

 the frog on its back, then examine the muscles on 

 the ventral side of the thigh. 



a. The sartorius, a narrow, band-like muscle cross- 

 ing the thigh obliquely. 



5. The adductor magnus, lying towards the me- 

 dian line from the sartorius, and partly covered 

 by the latter. 



c. The adductor longus, on the outer edge of and 

 partly covered by the sartorius. 



d. The rectus internus major and the rectus 

 internus minor, two muscles forming the in- 

 ner border of the thigh. 



Lay the frog on its ventral surface, and on the 

 dorsal side of the thigh find 



e. The triceps extensor femoris, forming the 

 outer edge of the thigh, and consisting above of 

 three parts, of which one, the rectus anticus 

 femoris, forms one side of the angle between 

 the side of the abdomen and the thigh, and 

 another, the vastus externus, appears about 

 midway between the first-named muscle and the 

 posterior end of the urostyle. 



f. The semimembranosus, lying towards the 

 median line from the vastus externus, and marked 

 by a tendon running obliquely across the muscle. 



g. The biceps femoris, lying between the vastus 

 externus and the semimembranosus. 



h. The pyriformis, passing down between the up- 

 per ends of the biceps and the semimembrano- 



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