242 MUSCLES OF THE LOWER EXTREMITY. 



surface with the muscles and tendons in the palm of the hand. By one 

 side with the metacarpal bone ; by the other with the corresponding palmar 

 interosseous. The abductor indicis is in relation by its palmar surface 

 with the adductor pollicis, the arteria magna pollicis being interposed. 

 The radial artery passes into the palm of the hand between the two heads 

 of the first dorsal interosseous muscle and the perforating branches of the 

 deep palmar arch, between the heads of the other dorsal interossei. 



Actions. The actions of the muscles of the hand are expressed in their 

 names. Those of the radial region belong to the thumb, and provide for 

 three of its movements, abduction, adduction, and flexion. The ulnar 

 group, in like manner, are subservient to the same motions of the little 

 ringer, and the interossei are abductors and adductors of the several fin- 

 gers. The lumbricales are accessory in their actions to the deep flexors : 

 they w r ere called by the earlier anatomists, fidicinii, i. e. fiddlers' muscles, 

 from an idea that they might effect the fractional movements by which the 

 performer is enabled to produce the various notes on that instrument. 



In relation to the axis of the hand, the four dorsal interossei are abduc- 

 tors, and the three palmar, adductors. It will therefore be seen that each 

 finger is provided with its proper adductor and abductor, two flexors, and 

 (with the exception of the middle and ring fingers) two extensors. The 

 thumb has moreover a flexor and extensor of the metacarpal bone ; and 

 the little finger a flexor of the metacarpal bone without an extensor. 



MUSCLES OF THE LOWER EXTREMITY. 



The muscles of the lower extremity^ may be arranged into groups cor- 

 responding with the regions of the hip, thigh, leg, and foot, as in the fol- 

 lowing table : 



HIP. 

 Gluteal Region. 



Gluteus maximus, * Gluteus 



Gluteus minimus, Pyriformb,^ 



Gemellus superior, Obturator internus, 



Gemellus inferior, Obturator externus. 

 Quadratus femoris. 



THIGH. 



interior Femoral Region. Internal Femoral Region. 



Tensor vaginae femoris, Iliacus internus, 



Sartorius, Psoas magnus, 



1 Rectus, Pectineus, 



Vastus internus, Adductor longus, 



V 7 astus externus. Adductor brevis, 



Crureus. Adductor magnus, 



Gracilis. 



Posterior Femoral Region. 



Biceps, 



Semitendinosus, 



Semimembranosus. 



