546 MESSRS. BEDDARD .VND MITCHELL ON THE [June 19, 



Exteiisor metuearpi radialis. — This has two heads, and the outer 

 of these is teudiuous and is connected with the tendon of the 

 patagiuui. The inner head is fleshy, but is covered with fascia on 

 the side turned towards the radius. The tendons from the two 

 heads remain separate to about half an inch from the common 

 insertion at the base of the metacarpal spine ; but the two tendons 

 are wrapped together by fascia. 



Ectepicondylo-radialis. — This is a strong muscle arising from 

 the outer condyle of the humerus, where it is covered by a ligament 

 passing from the outer condyle to the ulna. Its flat tendon of 

 origin is in common with that of the extensor digitorum communis. 

 It passes over to be inserted fleshy on to the second eighth of the 

 proximal surface of the radius. 



Ectepicondylo-ulnaris. — This is a stronger muscle than the last. 

 It arises tendinously from the outer condyle to the humerus, and 

 passing over to the ulna is inserted fleshy to the first third of its 

 radial face. 



Extensor metacarpi idnaris. — This arises from the outer condyle 

 of the humerus, its tendon being immediately external to that of 

 the foregoing. It is also connected by a strong band of fascia 

 with the proximal end of the ulna. It is inserted just above the 

 junction of the second and third metacarpals. 



Extensor digitorum communis. — The tendon of this arises from 

 the external condyle of the humerus. Its slender belly extends a 

 quarter of the length of the ulna, but it receives no fibres from 

 the ulna. After passing over a groove in the distal end of the 

 ulna its tendon forks, a short branch going to the phalanx of the 

 thumb, and a long branch to the base of the first phalanx of the 

 second digit. 



Extensor longiis pollicis. — This arises fleshy from four inches 

 after the first of the shaft of the radius and from the third 

 proximal inch of the ulna. The tendons from the two heads fuse 

 about half an inch from their common insertion to the tendon of 

 the extensor radialis metacarpi. 



Extensor indicus longus.—Oi the two heads of this the first 

 arises fleshy from the third quarter of the radius. The second is 

 much smaller and arises from the ligaments binding the radial 

 carpal to the distal ends of the radius and ulna. The insertion is 

 to the second phalanx of the index at its base, but it sends a broad 

 ligament to the base of the first phalanx. 



Pronator sublimis. — This arises proximal to the inner condyle of 

 the humerus, and its fleshy insertion is at the end of the first 

 third of the radius. 



Pronator profundus. — This has exactly the same length as the 

 sublimis. It arises from the inner condyle of the humerus, and 

 its tendon of origin sends a slip to the flexors. It is inserted 

 fleshy on to the radius and on to fascia covering the sublimis. 



Brachialis inferior. — This flat entirely fleshy muscle arises from 

 the disial end of the humerus, passes over the radius to be 

 inserted for an inch after the first half inch of the ulna. 



