MUSCLES OF THE FOOT. 



769 



FOURTH LAYER. 



The interossei plantares (Fig. 255) are three in number, 

 and occupy the interosseal spaces. They arise from the 

 base of the metatarsal bones, corresponding to the three 

 outer toes, and are inserted into the base of the first pha- 

 lanx of these toes at their inner side. Function. To ad- 

 duct the toes. 



MUSCLES ON THE DORSUM OF THE FOOT. 



The extensor brevis digitorum pedis (Fig. 256) arises ten- 

 dinous and fleshy from the anterior and outer part of the 

 os calcis, crosses the foot obliquely, and FIG. 256. 



divides into four delicate tendons. The 

 most internal is inserted into the base 

 of the first phalanx of the great toe ; 

 the other three join the tendons of the 

 extensor longus, which expand on the 

 back of the other toes. Function. To 

 extend the toes. 



The interossei dorsales (Fig. 256) are 

 four in number, on the back of the foot, 

 and resemble those on the hand in aris- 

 ing by two heads from adjacent sides of 

 the metatarsal bones. The first is in- 

 serted on the inner side of the first pha- 

 lanx of the second toe, and is an adduc- 

 tor. The other three are inserted on 

 the outer side of the second, third, and fourth toes, and 

 are abductors. 



SECTION II. 

 FASCIA OF THE INFERIOR EXTREMITY. 



The fasciae of the thigh are divided into the superficial 

 fascia and/ascia lata. 



FIG. 256 represents the muscles on the Dorsum of the Foot, a 6 c Extensor 

 brevis digitorum pedis. d Occasional supernumerary tendon, t Section of 

 tendons of Extensor communis. / Section of tendon of Extensor proprius pol- 

 licis. g Interossei muscles, h Superior astragalo scaphoid ligament. 



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