160 
MACROPODIDifc. 
Nearly at the same time Mr. Gray and M. Jourdan cha¬ 
racterised the present division as a distinct genus; but to Mr. 
Bennett is due the credit of having first drawn attention to 
the peculiarities presented by the M. penicillatus , which is 
the type of the section 1 . 
We have described the plain-inhabiting Kangaroos, and 
those which frequent the “scrubs;” the present section 
contains Kangaroos which are fitted for inhabiting the rocks. 
Whilst the Kangaroos of the plain have the fore part of the 
body slender and light, great strength in the hinder parts, 
combined with a long leg and foot, adapting them to flect- 
ness, the tail powerful, and assisting in the support of die 
long body, we perceive certain modifications in the form 
and structure of these parts in the Bock-Kangaroos which 
adapt them to their particular habitats: the body, more com¬ 
pact in form, requires but little assistance from the tail for its 
support, the leverage being less, and the hind feet are, though 
powerful, comparatively short, and remarkably rough beneath, 
being thickly covered over this part with hard tubercles, 
which no doubt prevent the foot from slipping: the nails of 
the two larger toes ore shorter than usual, and, indeed, in 
some of the species, scarcely project beyond the fleshy pads 
with which the toes are terminated, and on the upper surface 
of which the nails are placed. A long and slender foot, with 
long nails, as in the typical Kangaroos, it is obvious, would 
be ill adapted to an animal which has to leap to, and balance 
itself upon the small ledges of the rocks. The tail is large, 
but not thickened at the root, as in the plain Kangaroos; and, 
unlike the tail in those animals, it is clothed with long hairs, 
which, gradually increasing in length from the base of the 
tail, become very long and bushy at the opposite extremity: it 
servos to steady the animal in its leaps, and to balance the 
* See the Proceedings of the Zoological Society for January, 1835. 
