76 WILD NEIGHBORS CHAP. 
grass for its nest and takes it home in a bundle or 
thick wisp, grasped in the curled-up extremity of 
its strongly prehensile tail. Gould illustrates this 
in his monograph on the Macropodidz; and re- 
marks that, “as may be easily imagined, their ap- 
pearance, when leaping toward their nests with 
their tails loaded with grasses, is exceedingly 
amusing.” 
Referring again, for a moment, to the suggestion 
that the tail in the large wallabies, and creatures of 
similar proportions, is useful as a balancing-pole, it 
may be added that a similar explanation has been 
offered for the long tails that characterize most of 
the mice, especially those like the zapus and jerboa 
that are powerful leapers; at any rate, the service 
of a balancing-pole is unquestionably performed by 
the tails of many climbing and jumping mammals, 
and by all birds, as can be well seen in the act of 
alighting. As for the tufts common at the ends of 
many of the long-tailed mice, etc., it has been said 
that that was an extra advantage in the same direc- 
tion, comparable to the string of knotted papers 
that boys attach to their kites. 
Another quaint explanation of the tufted and 
brush-tipped tails will be noticed farther on. 
To many tree-haunting animals, such as the 
opossum, the South American forest monkeys, and 
some others, the tail has been modified into a most 
effective instrument for grasping and holding on, 
even in sleep, by the acquirement of what is called 
