THE CARPALIA. 



161 



defined, but cephalad it is continuous with the capitellum, the limits of the two surfaces 

 being indicated by a slight ridge. Ventrad, the two surfaces are nearly equal in extent, 

 but dorsad the capitellum gradually narrows and disappears as seen in Fig. 71, while 

 the trochlea continues upon the dorsal aspect of the bone and has a decidedly oblique 

 direction. 



THE CARPMJA (Fig. 6, 30, 47). 

 The bones of the carpus (wrist) have been enumerated in 84. 



References. In addition to the references given in 84, 85, see Gegenbaur, B ; 

 Straus-Durckheim, A, I, 518-524 ; Mivart, B, 96-98 ; Gray, A, 235-241 ; Quain, A, I, 

 90-93, 99 ; Chauveau, A, 88, 89 ; Chauveau (Fleming), A, 78, 80 ; Leyh, A, 177-183 ; 

 Flower, A, 252-260 ; Humphrey, A, 387-390. 



421. Explanation of Fig. 47. This represents the dorsal aspect of the carpus and 

 of the contiguous parts of the 

 metacarpalia of an Asiatic 

 lion seven months old, and 

 of two young dogs. The let- 

 tering is nearly uniform in 

 the three figures, but the 

 present description refers 

 only to the lion. 



P, I, M, A, Mi, the meta- 

 carpalia of the pollex, in- 

 dex, medius, annularis and 

 minimus ; p, the 0. pisi- 

 forme, which is really a sesa- 

 moid bone in the tendon of 

 the M. flexor ulnaris, and 

 not a true carpal element ; 



u, m, td and tm, the unci- FIG. 47. THE DORSAL ASPECT OF THE CARPAL REGION 

 forme, magnum, trapezoid OF A YOUNG LION (LARGEST FIGURE) AND OF Two 



and trapezium respectively, YOUNG DOGS. (From Wilder, 19, 301, Fig. 1.) 



forming the distal row of 



carpalia ; as stated in 84, the unciforme is supposed to represent two elements of the 

 typical or primitive carpus. 



The proximal row consists of but two cartilaginous pieces, commonly known as the 

 cuneiforme (py) and the scapho-lunare. Since cuneiforme has become well established in 

 the names of three of the tarsal bones, Ave have, upon the suggestion of Prof. O. C. Marsh 

 and in accordance with the custom of some European anatomists, substituted therefor the 

 term pyramidale, which was employed by Straus-Durckheim (A, I., 520), This element 

 represents the ulnare of the primitive carpus. 



The larger proximal piece is a single mass of cartilage, but a section shows that ossifi- 

 cation has begun from three separate centers. The two larger correspond to the scaphoides 

 (sc) and the lunare (1) of man, and to the radiale and intermedium of the primitive carpus. 

 The third and smaller center (ce) probably represents the centrale of the primitive carpus, 

 which is not distinct in man. 



So far as appears from the figure of Mivart (B, Fig. 60), the carpus of the cat is essen- 

 tially similar to that of the lion. 

 11 



