292 



THE MANUS. 



[CHAP. 



In the RODENTIA, the scaphoid and lunar are very 

 generally united (as in Castor, Dasyprocta, Hydrochcems, 

 Capromys, Sciurus, Arctomys, Mus, &c.), but not in all. An 

 os centrale is present in many, as Lepus, Dasyprocta, Hydro- 

 choerus, Capromys, and Castor, while in other genera it is 

 absent. There is very frequently an accessory ossicle on the 

 radial side of the carpus, which is particularly large in the 

 Beaver (Fig. 96). There are nearly always five digits, with 



\s 



FIG. 97. Bones of the manus of Cape Hyrax (Hyra.v capensis), nat. size. 



the normal number of phalanges, though sometimes (as in 

 Hydrochcenis} the pollex is rudimentary or suppressed. 



HYRAX and the ELEPHANTS, together with various extinct 

 forms (Dinoceras, Coryphodon, Toxodon, &c.), are united 

 by Professor Cope under the name of Subungulata, in 

 opposition to the Ungulata vera. In all of these the 

 bones of the proximal and distal rows of the carpus retain 

 their primitive or more typical relation to each other. The 



