"a 
“a 
ORGANS OF LOCOMOTION. 965 
trast to these antics is the ‘‘ measured step and slow’ 
of the hoofed quadrupeds to whom the faculty of 
climbing is totally denied! Yet here again we have 
numerous modifications of pace, from the slow and 
stately walk of the elephant and the ox, to the fiery 
impetuosity of the horse, and the bounding spring 
of the elegant antelope. Yet these are not the most 
extraordinary of nature’s contrasts. The continent 
of Australia presents us with two other modes of 
progression, totally different from those just men- 
tioned, and almost confined to the quadrupeds of 
the southern hemisphere. These belong to the 
phalangers and the kangaroos: the first have their 
representatives in the New World, in the squirrels. 
The phalangers, in fact, are flying quadrupeds ; not, 
indeed, from possessing wings, but from having 
their feet so united by a thin expansive skin, that 
they can take prodigious leaps from tree to tree, so 
as to give them the appearance, to an ordinary 
observer, of flying. This winglike membrane, in 
short, acts and folds up like a parachute or umbrella, 
and supports the animal in the air when it otherwise 
would fall upon the ground. In the kangaroos, on 
the other hand, the power of leaping is developed in 
a most remarkable manner: their fore-feet are so 
short as to be perfectly useless in running, but 
their hinder are enormous; and with these, assisted 
by their thick and powerful tail, they proceed by a 
succession of amazing bounds or rather leaps, re- 
peated so fast, and so wide, that these animals, with 
two feet only, will generally escape from any other, 
even a horse, that has four. Two other modifications — 
of foot remain to be mentioned: the first belongs 
