THE MUSCLES 83 



Extensor carpi ...... Stannius (1854-6). 



Extensor carpi s. metacarpi radialis und ulnaris . Riidinger (1868). 



Humero-ulnaris dorsalis . . Hoffmann (1873-8); Rylkoff (1924). 



filevateur cubito-carpien (64-5) .... Perrin (1899). 



Ulnaris externus ...... Sieglbaur (1904). 



This muscle forms the ulnar counterpart of the foregoing. It arises 

 from the extensor border of the epicondylus lat. hum., and from the 

 raphe mentioned above as occurring between this and the previous 

 muscle. It is inserted along the central portion of the lateral face of 

 the ulna (= M. ext. antibr. ulnaris) and on the ulnare+intermedium 

 (= M. ext. carp, ulnaris). 



Innervation: From the N. extensorius caudalis. 



Function : It is the true extensor of the fore-arm. 



All three of the foregoing muscles are closely associated at their 

 origin. The separation of the two latter muscles into 'antibrachii' and 

 'carpi' portions is to be regarded as in an incipient state in the Sala- 

 mander, and varies in different individuals. They are usually separ- 

 able distally, since the 'antibrachii' portions have fleshy insertions on 

 the radius or ulna, while the 'carpi' portions are gathered into strong 

 tendons before their insertions. 



M. abductor and extensor digiti primi (m.a.e. i .). Sieglbaur (i 904). 



(?) Hallici proprius 

 Cubito-sus-pollicien 

 Extensores und Adductores 

 Extensor digiti I 

 Extensor brevis 



. Carus(i828). 



. Duges(i834). 



Stannius (1854-6). 



Rudinger(i868). 



Mivart (1869). 



Uppermost part of the deep stratum s. Supinator manus 



Humphry (1872). 

 Ulnari-phalanx II dorsalis .... Hoffmann (1873-8). 

 Abductor metacarpi II -|-extensor digiti II brevis superficialis 



Eisler (1895). 



Court adducteur du premier metacarpien (69)+Court extenseur du 



premier doigt (70 et 71) ..... Perrin (1899). 



Abductor digiti secundi-j-Extensor brevis digiti II . Osawa (1902). 



This muscle group arises mainly from the combined ulnare+inter- 

 medium^ while a few fibres (possibly representing the M. extensor 

 brevis digiti I profundus ^) take their origin from the os centrale. It 

 passes obliquely across the wrist and is inserted on the outer edge of 

 the proximal end of the first metacarpal (= M. abductor digiti I), 

 and on the distal end of the same bone (= M. extensor digiti I). 



Innervation-. From the N. dorsalis manus intermedius. 



Function: It is the extensor muscle of the first digit. It would 



