148 THE MYOLOGY OF THE RAVEN. 



tomists for the foot, but it is incorrectly termed, as it 

 should be called the extensor proprius hattucis. 



86. The flexor brevis pollicis arises from the shaft of 

 the mid-metacarpal bone of the carpo-metacarpus, just 

 below the anchylosed first or pollex metacarpal. Its 

 fibres converge as they pass down behind the thumb 

 joint, to become converted into a delicate tendon which 

 is inserted into the distal apex of that phalanx. 



Thus we see that the pollex of the Raven is supplied 

 with two extensors and one flexor. When the wing is 

 fully extended and the tendon of the extensor metacarpi 

 radialis longior is on the stretch, and at the same time 

 the tendinous slip from the extensor digitorum com- 

 munis is pulling on this digit, it is held in full extension, 

 by virtue of the several methods of attachment of the 

 muscles, and the wing feathers attached to it are in this 

 way so spread as to present the greatest amount of 

 superficial area to the atmosphere. When the wing is 

 closed, the more delicate flexor of the thumb draws that 

 joint down again towards the metacarpus, and is 

 sufficiently powerful to retain it in that position. 1 



87. The flexor minimi digiti? instead of going to 

 the little finger as in a five-fingered hand (as in Homo], 

 it is inserted into the smallest finger-joint of the bird's 

 hand, which, as we know, corresponds with the medius. 



1 We find, upon referring to Selenka's excellent work in Bronn's 

 Thier-Reichs (vi. Band, p. 138, No. 71), that he designates this muscle 

 as ihejlexor pollicis brevis, while Gadow describes it briefly as the 



M. ADDUCTOR POLLICIS (No. 101) (loc. dt., pp. 291, 292). 



2 Here we have the muscle that Watson defined as the flexor 

 minimi digiti (p. 99), and which has been amply recognized by other 

 writers. Gadow made it his (No. 102) M. FLEXOR DIGITI in., and 

 remarked that " Bei Corvidce ist der Muskel nur schwacli ent- 

 wickelt und, wenn iiberhaupt vorhanden, rnehr auf den dorsal- 

 ulnaren Band beschrankt " (loc. cit., p. 293). 



