AND PHYSIOLOGY. 



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tibia near to its upper extremity. Spoken of together, these 

 muscles are called the Quadriceps Extensor Femoris. The 

 tendon is one of the strongest in the body, and has inclosed 

 within it the patella, which bears the same relation to the 

 tendon as the pulley does to the cord which passes over it. 

 The action of these muscles extends the leg, as in walking, 

 running, or lifting the foot, and also places the femur in a line 

 above the tibia, when the latter is made the fixed point. 



255. S art o riii s Muscle —The Sartorius or Tailor's mus- 

 cle is a very long and slender muscle commencing at the an- 

 terior portion of the innominatum, and, descending downwards 

 and inwards, is inserted into the upper part of the inside of 

 the tibia. The obvious action of this muscle will be to bend 

 the leg somewhat backwards, and then to carry it across its 

 fellow, as is done by the tailor when seating himself for work 

 on his bench. 



256. Tensor Vagina; Femoris. — A muscle already alluded 

 to — the Tensor Vaginas Femoris, or stretcher of the sheath of 

 the thigh — arises at the upper and front portion of the inno- 

 minatum, and is inserted into the very strong fascise of the 

 thigh, its use being to assist the muscles in their action, by 

 increasing the tonic pressure upon them. 



257. Muscles of the Posterior Part of the Thigh.— 

 The muscles found upon the posterior part of the femur 

 and antagonizing the compound muscle in front, are four in 

 number, taking their origin from the ischium and pubes, and 

 being inserted into the broad head of the tibia. Their ten- 

 dons make those portions of the thigh which are familiarly 

 known as the ham-strings. Their names are the Biceps, 

 Gracilis, Semi-tendinosus and Semi-membranosus. 



When taken together, what is the muscle called ? What bone is imbedded in the ten- 

 don of the Quadriceps Extensor Femoris ? 255. Describe the Sartorius or Tailor's mus- 

 cle. 256. What is the Tensor Vaginae Femoris of service for? 257. How many muscles 

 act as antagonists to the Quadriceps, etc. ? Give their names. 



