872 MR. ST. GEORGE MIVART ON THE [ Dec. 6, 
pollex distad and radiad of the insertion of the extensor ossis meta- 
carpi pollicis. 
Flexor brevis minimi digiti. Another small muscle arises from 
the ulnar side of the palmar ossicle, and is inserted into the ulnar 
side of the fifth digit. 
Adductor digiti tertii (fig. 9, A). This springs from the liga- 
ment connecting the third and forth metacarpals, and is inserted into 
the ulnar side of the third digit. 
Adductor digiti quarti (fig. 9, M+). Another small muscle arises 
from the same ligament, connecting the third and fourth metacarpals, 
and is inserted into the radial side of the fourth digit. 
The extensores metacarporum are very numerous, but are all short 
muscles, except the one which goes to the pollex. 
Lxtensores I. and II. or extensor ossis metacarpi pollicis* (figs. 
8, 9, 10, 11 & 12, M.P). This is a very large and even a double 
muscle, like the homotypal muscle of the pes. The longer part arises 
(in intimate connexion with the deeper part of the supinator longus) 
from the lower end of the humerus, close to its articulation with the 
radius. Passing downward, it joins the shorter part a little above 
the wrist. This shorter part springs from the radiad aspect of the 
ulna for its whole length. Passing downward and radiad, it unites 
with the longer part, and the united muscle is inserted into the 
radial aspect of the dorsum of the distal end of the first metacarpal 
bone. 
Fig. 16. 

Part of deepest flexor surface of right forearm. 
B. Biceps. B.A. Brachialis anticus. FD. Flexor profundus digitorum. 
P. A, Pronator accessorius. P. Q. Pronator quadratus. 
Extensor m. III. (fig. 9, E*). This little muscle arises from the 
extensor aspect of the styloid process of the radius, and is inserted 
into the distal part of the dorsum of the first metacarpal. 
Extensor m. IV. (figs. 9 & 11, £*). This takes origin just be- 
neath and beside the last-described muscle, and is similarly inserted 
into the second metacarpal. ’ 
The extensor m. V. (figs. 9 & 11, E°) arises just beneath and be- 
side the last described, and is similarly inserted into the third meta- 
carpal. A few of its fibres take origin from the ulnar carpal ossicle. 
The extensor m. VI. (figs. 9 & 11, £°) springs from the central 
carpal ossicle, and from the dorsum of the first three metacarpals. 
* Meckel, 7. c. p. 382. 
