ADD UCTOR II A LL UCIS 



383 



into tlie iiiiRT and outer part of the lower Ijorder of the l)ase of the firt^t ])lialanx, 

 they are blended with the tendons of the alxluctor and the adductor hallueis. 



Nerve-supply. — From the internal ])lantar division of the ]»osterior tiliial 

 nerve, by tilauients which enter the under surface of the nuiscle near the middle of 

 its inner border. 



Action. — To flex and sli,i;htly adduct the first i)halanx of the great toe. The 

 sesamoid bones give a slight ol)liquity to its insertion, and so enable it to act with 

 more power; at the same time they form a groove in which the strong tendon of the 

 fl(^xor longus hallucis plays. They also form a somewhat elastic support when the 

 weight is placed upon the ball of the foot. 



Relations. — Superficially, the abductor hallucis, the tendon of the flexor longus 

 hallucis, and the inner tendons of the flexor longus digitorum with the lumbricales; 

 dee])ly, the interossei and the termination of the external plantar vessels and nerve. 



Variations. — A small slip is occasionally given to the first phalanx of the second toe. 



Fig. 295. — Third Layer of the Muscles of the Sole. 



Long plantar ilong inferior 

 caleaueo-cuboid) ligaineat 



Part of abductor minimi digiti 



Flexor brevis minimi digiti 



TrauBversus pedis — 



Divided tendons of flexor brevis 

 digitorum 



Tendon of flexor longus digitorum 



Tendon of the flexor longus 

 hallucis 



2. ADDUCTOR HALLUCIS 



The adductor hallucis — named from its action up(jn the great toe — is a tri- 

 angular sheet, the a]>ex of which is directed forwards and inwards. 



Origin. — (1) The continuation forwards of the long j)lantar ligament which 

 forms the sheath of the ])eroneus longus tendon; (2) the under surface of the bases 

 of the second, third, and fourth metatarsal bones. 



