344 THE MUSCLES 



Nerve-supply. — Through the eighth cervical nerve, from the deep branch of 

 the uhiar nerve which sends filaments to the ui)per part of its deep and ulnar 

 surface. 



Action. — To tlex tlie first phalanx of the Httk* finger. 



Relations. — Superficially, the hypothenar part of the palmar fascia, the lower 

 part of the abductor minimi digiti, and the superficial palmar arch; deeply, the 

 opponens minimi digit! and the fifth metacarpal bone; and to its radial side lie 

 the flexor tendons of the little finger. This muscle is closely connected with the 

 previous one, from which it is separated above by the deep palmar branches of 

 the ulnar artery and nerve. 



Variations. — It may foil, or be bleuded with the abductor or opponens minimi digiti. An 

 aecessorj' slip may come to it from the lower third of the ulna at its inner border, from the 

 tendon of the flexor carpi ulnaris, or the deep foscia of the forearm. 



3. OPPONEXS MINIMI DIGITI 



The opponens minimi digiti (= flexor ossis metacarpi minimi digiti) — named 

 from its action — is a triangular fan-shaped sheet. 



Origin. — (1) From the hook of the unciform bone deeper than the preceding; 

 (2) from the adjacent part of the anterior annular ligament. 



Insertion. — The wdiole of the ulnar border and part of the head of the fifth 

 metacarpal bone. 



Structure. — Arising by short tendinous fibres, the fleshy liundles diverge down- 

 wards and outwards, and are inserted by short tendinous fibres. 



Nerve-supply. — Through the eighth cervical nerve, from the deep branch of 

 the ulnar nerve which sends filaments to the upper part of its ulnar aspect. 



Action. — To flex the fifth metacarpal bone, and at the same time slightly to 

 adduct it. This movement is observed Avhen the palm is cupped, as when the hand 

 is used to lift water to the mouth. 



Relations. — Superficially, the abductor and the flexor brevis minimi digiti; 

 and deeply, the interossei of the fourth interspace, and the deep branches of the 

 ulnar artery and nerve. 



Variations. — It may receive a slip from the deep fascia of the forearm. 



THE 3IUSCLES AND FASCIJE OF THE THIGH 



Superficial fascia. — The greater part of this is of loose adipose tissue, and, 

 without any dee]) connections, is continuous with the superficial fascia of the 

 al)domen and l)ack. In the upper and front part of the thigh a deep layer of a 

 more membranous structure may be distinguished, and this has deep connections 

 where the lower liml) joins the trunk, Ijcing attached to the crest of the ilium and 

 to the fascia lata just below its insertion into Pou])art's ligament and the rami of the 

 pubis and ischium. Below the inner half of Pou})art's ligament several lymphatic 

 glands are arranged longitudinally lietween these two layers of the superficial fascia. 



The deep fascia or fascia lata is a very strong layer of fibrous tissue, the fiV)res 

 of which are arranged for the most part transversely as an aponeurosis of invest- 

 ment; but many of them, especially upon the outer side where it is much thicker, 

 are longitudinal, and serve for the insertion of important muscles. The Avhole of 

 the deep fascia forms a strong cylindrical tube investing all the muscles of the thigh. 

 It is attached above, in the groin, to Poupart's ligament, where it blends with the 



