THE RABBIT. 357 



common with the adductor magnus ( 443), and passes 

 outwards, widening as it goes : the two heads unite, and are 

 inserted by a strong and extensive fascia into the distal end 

 of the femur and proximal end of the tibia. Cut through 

 both heads and reflect : it will be seen that the posterior 

 head has a second origin in the form of a flat tendon arising 

 in common with the semi-membranosus ( 442) from the 

 anterior end of the tuber ischii. 



442. The semi-membranosus (s.m), forming the 

 posterior edge of the thigh : it arises from the tuber ischii in 

 common with the accessory tendon of the posterior head of 

 the biceps, and is inserted by the same fascia as the gracilis 

 into the proximal part of the pre-axial border of the tibia : 

 from the distal end of its posterior edge proceeds a long 

 tendon which passes along the inner side of the shank and 

 joins the tendo Achillis ( 460) : cut through and reflect. 



443. The adductor magnus (ad.m), a large fleshy 

 muscle in the posterior region of the thigh, fully exposed by 

 the removal of the gracilis, which covers its inner face, and 

 of the semi-membranosus and biceps, which cover its outer 

 face : it arises from the posterior edge of the ischium and 

 tuber ischii, and is inserted into the inner side of the distal 

 end of the femur and inner condyle of the tibia. 



444. The semi-tendinosus (j./), seen by separating 

 the fibres of the adductor magnus in which it is embedded : 

 it is a long spindle-shaped muscle, arising from the tuber 

 ischii and inserted by a long tendon, which emerges from 

 the adductor magnus near the distal end of its outer surface, 

 into the inner condyle of the tibia : cut through and reflect 

 both semi-tendinosus and adductor magnus. 



445. The adductor longus (ad. I), a large, somewhat 

 triangular muscle, forming the main part of the mass of flesh 

 still left posterior to the femur : it arises from the whole of 



