THE SKELETON. 



59 



from the cuneiform and articulates with the ulna and 

 cuneiform. The trapezium is the smallest bone of the 



carpus. It is crescentic in 

 shape and articulates with 

 the scapholunar, trapezoid, 

 and first and second meta- 

 carpals. The trapezoid is 

 almost as small as the trape- 

 zium. It is distinguished by 

 its flatness. It articulates 

 with the scapholunar, mag- 



A. B. 



FIG. 36. 



A, Dorsal aspect of left manus of cat: a, First phalanx of the pollex; b, 



second or terminal phalanx; en, cuneiform; h, head of fourth meta- 

 carpal; m, magnum; mt, metacarpal 4; n, claw; pi, pisiform; s, 

 sesamoid bone; st, scapholunar; td, trapezoid; tm, trapezium; u, 

 unciform; i, 2, and 3, first, second, and third phalanges of the 

 middle digit. 



B, Generalized type of carpus as found in lower vertebrates : c, Centrale ; 



i f intermedium or lunare; r, radiale or scaphoid; ra, radius; m, 

 metacarpals; u, ulnare or cuneiform; ul, ulna; I, carpalia I, or 

 trapezium; 2, carpalia 2, or trapezoid; 3, carpalia 3, or magnum; 

 4 and 5, carpalia 4 and 5, or unciform. 



num, second metacarpal, and trapezium. This bone is not 

 visible on the palmar surface of the wrist. The magnum 

 articulates with the scapholunar, trapezoid, unciform, and 

 second, third, and fourth metacarpals. The unciform can 

 be recognized by its wedge shape. It articulates with the 

 scapholunar, cuneiform, magnum, and fourth and fifth meta- 

 carpals. Each carpal bone develops from a single center 

 except the scapholunar, which develops from two centers. 



