﻿128 PLEISTOCENE MAMMALIA. 



CHAPTER XIII. 

 Carpus, PI. XX, figs. 1, V, 2, 3, 4, 5, 5'. 



CONTENTS. 



§ 1. Scaphoido-Iunare. 

 a. Description. 

 /3. Measurements, 

 y. Definition from that of Ursus. 



§ 2. Pisiform. 



a. Description. 



j3. Measurements. 

 § 3. Unciform. 



a. Description. 



/3. Measurements. 



In describing the bones of the carpus we shall consider the anterior or dorsal surface 

 as that which is naturally so in all quadrupeds ; the palmar and inferior or posterior as 

 synonyms denoting the same portion of the bone. 



The carpus in the genus Eelis is composed of seven bones, besides the small one which 

 has no independent existence in human anatomy, called by Straus-Durckheim the ' phacoid.' 

 The scaphoido-lunare, the cuneiform, and pisiform, compose the upper or proximal row ; 

 the trapezoid, the trapezium, the magnum, and unciform, the lower or distal. Of these we 

 have only met with the scaphoido-lunare, the unciform, and pisiform, in Felis spelcea. 



1 . Scaphoido-lunare (PI. XX, figs. 1, 1', 2). — 1 a. Description. — The scaphoido-lunare is 

 by far the largest and most important bone in the carpus; it extends throughout the whole 

 width of the joint, and forms almost the sole means of attachment between the fore paw and 

 the forearm. It is very massive and is roughly quadrangular in plan, with a large and strong 

 tubercle projecting from the postero-internal angle (fig. 1', e) ; it is broader than long, and 

 much thicker externally than internally. The proximal or radial articulation (figs. 1, 

 2, a, b), which covers the whole of that surface of the bone with the exception of that 

 portion which is opposite the tubercle is convex, traversed intero-posteriorly by a depres- 

 sion (figs. 1, 2, b) running from behind forwards and inwards. On its external edge is a 

 very small articulation for the upper edge of the pisiform, which just touches it at that 

 point (figs. 1, 2, c). 



The tubercle (fig. 1' e) is a somewhat pyramidal or conical mass, projecting diagonally 



