256 THE MANUS. [chap. 



and 2 ; the intermedium is in a line with the centrale and 

 carpale 3, which together form a median axis of the hand, 

 while the itlnare has also two bones articulated with il 

 distal end, viz. carpale 4 and 5. Each of the carpals of th< 

 distal row supports a metacarpal. 



In the carpus of the Mammalia, there are usually twc 

 additional bones developed in the tendons of the flexor 

 muscles, one on each side of the carpus, which may be 

 called the radial and ulnar sesamoid bones ; the latter is 

 most constant and generally largest, and is commonly known 

 as the pis/form bone. The fourth and fifth carpals of the 

 distal rows are always united into a single bone, and the 

 centrale is often absent. As a general rule all the other 

 bones are present and distinct, though it not unfrequently 

 happens that one or more may have coalesced to form 

 a single bone, or may be altogether suppressed. 



The table below shows the principal names in use for the 

 various carpal bones. Those in the second column, being 

 most generally employed by English anatomists, will be 

 adopted in the following pages : — 



The metacarpal bones, with the digits which they sup- 

 port, never exceed five in number, and are distinguished by 

 numerals, counted from the radial towards the ulnar side. 

 The digits are also sometimes named (I) pollex, (II) index, 

 (III) meditts, (IV) annularis, and (V) minimus. One or more 



