THE TROPICAL FOREST Lit 
to permit them to pass from one tree to another shows 
that their natural habitat is the dense forests where 
tree is bound to tree by lianes. 
Among the special features we may note the nature 
of the coat, the individual hairs having a fluted surface, 
on which algae lodge, and so give the animals the 
appearance of a lichen-covered branch. The fingers 
are converted into mere hooks, the tail is a stump, 
a common feature in such arboreal animals as have 
not prehensile tails, or do not require to use the tail 
as a balancing organ after the fashion of squirrels and 
tree-shrews (cf. bears, anthropoid apes, &c.). We have 
already spoken of the elongation of the forelimbs in the 
sloths (p. 95). The food consists of leaves and fruits and 
the animals do not drink. The usual position is hang- 
ing back downwards from the branches of trees, and the 
animals sleep rolled up in a ball with the head tucked 
between the arms. Like many helpless forms they are 
active only at night (see Fig. 32). 
The South American ant-eaters are also forest animals, 
the large form called Myrmecophaga jubata being strictly 
terrestrial, while the little two-toed ant-eater (Cyclo- 
turus didactylus) is arboreal, and except that it has 
a prehensile tail and lives upon insects, has a curious 
adaptive resemblance to a sloth, both in the struc- 
ture of its limbs and in appearance. The hairy ant- 
eaters of South America are ‘replaced in India and 
Africa by the scaly ant-eaters or pangolins (Manis), but 
though some of these are partially arboreal, most are 
found in rocky country, where they burrow in the 
ground, 
Not a few of the marsupials have acquired arboreal 
habits. Thus the tropical forests of New Guinea and 
Queensland are inhabited by tree kangaroos, which have 
