430 C. J, Sundevall on the W'niys of Birds. 



the finger aud turns it a little so that the tips of the largest 

 feathers are turned downwards; it likewise flexes the thumb. 

 (Tlie course of the sinew is analogous to that of the Fl. dig. 

 prof. No. 11.) 



4. Extensor indicts proprius (essentially an extensor pro- 

 fundus, answering to the flexor profundus), beneath the 



preceding^ nearly between the radius and ulna, attached to 

 the radius. — The sinew runs to the anterior margin of the 

 metacarpus through the same sheath as the preceding, passes 

 over the bend of the latter^ and is attached at the base of 

 the second phalange on the outer side^ near the flexor 

 profundus. 



5. Extensor carpi ulnaris, visible externally near No. 3, is 

 always firmly united with the ulna by cellular tissue, behind 

 No. 6, and usually commences in common with the latter 

 from the condylus externus, or on the surface of its basal 

 sinew. — The sinew passes backAvard over the apex of the 

 ulna, and attaches itself at the base of the os metacarpi on 

 the outer side. (Called by Schopss, " abductor metacarpi.") 



b. Short muscles (attached to the radius or ulna). 



6. Humero-ulnaris externus, commences in a point, with 

 a short, strong sinew, upon the condylus externus ; it is 

 large, but quite covered by the preceding ; it is broadly 

 attached and generally spread out upon the anterior surface 

 of the ulna (near the lig amentum inter osseum). It seems 

 to serve both as a flexor and to give firmness to the 

 joint. {CaWcd flexor profundus antibrachii by Schopss ; see 

 further on under No. 15.) Leaving out of consideration 

 some diff'erence in position, it might be regarded as the 

 same as the anconeus parvus in man. Except this^ there is 

 nothing with which it can be compared. I have, however, 

 adopted a new name for it; for the reason of this see 

 further on. 



7. Supinator radialis is only one in birds, concealed under 

 No. 1, in front of the radius ; it springs from the condylus 

 externus, united with No. 3, but beneath it ; and is attached 

 to the middle of the anterior surface of the radius without a 



