ADDUCTOR POLLICIS. 247 



By its external surface with the flexor ossis metacarpi and metacarpal 

 bone. By its inner surface with the tendons of the long flexor muscles 

 and first lumbricalis. 



The ADDUCTOR POLLICIS is a triangular muscle ; it arises from the 

 whole length of the metacarpal bone of the middle finger ; and the 

 fibres converge to its insertion into the base of the first phalanx. 



Relations. By its anterior surface with the flexor brevis pollicis, 

 tendons of the deep flexor of the fingers, lumbricales, and deep palmar 

 arch. By its posterior surface with the metacarpal bones of the index 

 and middle fingers, the interossei of the second interosseous space, and 

 the abductor indicis. Its inferior border is subcutaneous. 



Ulnar, or Hypothenar Region. 



Palmaris brevis, 

 Abductor minimi digiti, 

 Flexor brevis minimi digiti, 

 Flexor ossis metacarpi (adductor). 



Dissection. Turn aside the ulnar flap of integument in the palm of 

 the hand ; in doing this, a small subcutaneous muscle, the palmaris 

 brevis will be exposed. After examining this muscle, remove it with 

 the deep fascia, in order to bring into view the muscles of the little 

 finger. 



The PALMARIS BREVIS is a thin plane of muscular fibres which 

 arises from the annular ligament and palmar fascia, and passes trans- 

 versely inwards, to be inserted into the integument on the inner border 

 of the hand. 



Relations. By its superficial surface with the fat and integument 

 of the ball of the little finger. By its deep surface with the internal 

 portion of the palmar fascia, which separates it from the ulnar artery, 

 veins, and nerve, and from the muscles of the inner border of the hand. 



The ABDUCTOR MINIMI DIGITI is a small tapering muscle which 

 arises from the pisiform bone, and is inserted into the base of the first 

 phalanx of the little finger. 



Relations. By its superficial surface with the internal portion of 

 the deep fascia and the palmaris brevis ; by its deep surface with the 

 flexor ossis metacarpi and metacarpal bone. By its inner border with 

 the flexor brevis minimi digiti. 



The FLEXOR BREVIS MINIMI DIGITI is a small muscle arising from 

 the unciform bone and annular ligament, and inserted into the base of 

 the first phalanx. It is sometimes wanting. 



Relations. By its superficial surface with the internal portion of 

 the palmar fascia, and the palmaris brevis. By its deep surface with 

 the flexor ossis metacarpi, and metacarpal bone. Externally with the 

 abductor minimi digiti, from which it is separated near its origin by 

 the deep palmar branch of the ulnar nerve and communicating artery. 

 Internally with the tendons of the flexor sublimis and profundus. 



