THE LIMBS. 157 



numerals I. to V., counted from the radial to the ulnar 

 side in the fore limb, from the tibial to the flbular 

 on the hind limb. They are also sometimes named 

 (I.) pollex or thumb (fore limb), hallux (hind limb) ; 

 (II.) index; (III.) medws ; (IV.) annularis;* and 

 (V.) minimus. Though five is the complete number, 

 one or more may be in a very rudimentary condition, 

 or altogether suppressed. If one is absent, it is most 

 commonly the first; next follows the fifth. The 

 third is never lost, although either the second or 

 fourth, or both, may be absent. 



In both limbs the normal arrangement is that 

 the carpus or the tarsus, as the case may be, supports 

 five long bones placed side by side, called the meta- 

 podials (or metacarpals in the fore limb, metatarsals 

 in the hind limb), and to the end of each of these are 

 three distinct bones called phalanges, except in the 

 case of the pollex and hallux, which have only two. 

 The terminal or distal phalanges of the digits are 

 often specially modified to support the external horny 

 covering usually present, called nail, claw, and hoof, 

 according to its form and size, and hence are spoken 

 of as the " ungual phalanges." 



This portion of the limb, being usually more or 

 less broadened and flattened, presents two surfaces 



* Being in man the finger on which the ring is commonly 



