DISSECTING MANUAL. 



joined together by t\vo oblique bands. Insertion; each tendon 

 spreads out over the metacarpo-phalangcal joint of its finger, 

 forming its posterior ligament, and over the first phalanx. At 

 the lower end of this phalanx it splits into median and lateral 

 slips, which pass over the back of the first inter-phalangeal joint 

 and form the posterior ligament. The median slip is inserted 

 in the back of the base of the second phalanx ; the lateral slips 

 then unite, pass over the next joint, and are attached to the 

 base of the terminal phalanx. [349] 



Extensor Minimi Digiti. Origin; external condyle, by the 

 common tendon; fascia over it; intermuscular septa. In- 

 sertion; expansion of Extensor communis tendon on back of 

 first phalanx of little finger. [350] 



Extensor Carpi Ulnaris. Origin; (humeral head) external 

 condyle, by the common tendon; fascia over it; intermus- 

 cular septa; (ulnar head) middle two-fourths of posterior bor- 

 der of ulna, through the deep fascia. Insertion ; back of base 

 of fifth metacarpal. [350] 



Anconeus. Origin; external condyle, by a separate tendon. 

 Insertion ; triangular surface on outer side of olecranon proc- 

 ess and back of ulna, down to oblique line. [350] 



Deep Layer. 



Supinator Radii Brevis. Origin; external condyle; orbicu- 

 lar and external lateral ligaments of elbow ; triangular surface 

 on ulna below lesser sigmoid cavity; fascia over it. Course; 

 envelops the upper part of the radius. Insertion ; anterior and 

 outer surfaces of radius, extending forward to the bicipital tu- 

 berosity, upward to the neck, and downward to the oblique line 

 and insertion of the Pronator radii teres. [351] 



Extensor Ossis Metacarpi Pollicis. Origin; posterior sur- 

 faces of radius and ulna, below the preceding; intervening 

 portion of interosseous membrane. Insertion; outer side of 

 base of first metacarpal. [351] 



[174] 



