218 
Dr. Kidd on the 
pose : for instead of being covered with down or hair, like 
all the rest of the limb, they are hard, and have a perfectly 
polished surface ; doubtless in order to prevent as much as 
possible the adhesion of the earth through which the animal 
is to make its way ; they have each of them sharp but strong 
points, which proceeding from a broad base are thus ren- 
dered more effectual. In each also of the claws one of the 
edges is sharp, while the other is comparatively blunt ; and 
all the cutting edges, as also the terminating points, are 
directed downwards. Their outer surfaces are slightly con- 
cave both in the longitudinal and transverse direction ; so 
that all together they form a scoop as it were, by which the 
earth that has been scraped off by the points is moved out of 
the way. They are also each of them divided longitudinally 
on their concave side by three or four slight ridges ; so that, 
though highly polished, their surface is not absolutely 
smooth : and thus being concave and uneven, they are more 
apt to retain particles of the excavated earth ; which, by 
filling up the indentations of the claws would necessarily 
impede their due action. To obviate this inconvenience, an 
exceedingly curious instrument is attached to the upper part 
of the concave surface of this member : this instrument con- 
sists of two claws, closely resembling those already described, 
having by their side a small brush as it were, which termi- 
nates in two spines. These two claws, together with the 
piece bearing the spines, arise from a single piece, or handle, 
which is articulated in such a manner, as to move in a plane 
parallel to that in which the four claws are placed ; but in a 
direction opposite to that in which they are moved : they 
are also placed in such a manner that their points and cutting 
