‘Nor 2: ] THE HARD PARTS OF THE MAMMALIA. 169 
of the carpal bones of the 
first row have become ob- 
lique, outwards and for- 
wards, in the Artiodactyla, 
except the Camelidz ; and 
Hemee the intercarpal 
crests of the radius have 
become oblique in the 
same way. III. The bones 
of the first carpal row have 
come to occupy the posi- 
tions above the lines of 
separation between those 
of the second row, thus 
producing diplarthrism. 
IV. The bones of the first carpal row have 
‘moved to a position external to the axial lines 
of their corresponding digits (e.g. the lunar 
is external to the axis of the third metapodial 
in Perissodacty- 
la (Fig. 16) and 
Artiodactyla 
(Figs. 12-15), 
instead of above 
it as in Taxeo- 
poda (Fig. 16). 
C 
Figure 16, — Manus of Phenacodus (4) and Perissodactyla; viz. : 
B. Hyracothe- 
rium venticolum, C. Hyrachyus agrestis; D. Rhinocerus unicornis; E. Equus 
caballus ; all showing external transposition of os dunare, L. P. Line of strain in 
plantation; R. Do. in recover. 
wr \ 
