THE FLYING SQUIRREL. 135 
course constantly grow less towards the centre; yet through this 
narrow space which passes, when the wheel is at full speed, in the 
sixteenth of a second, they dart in and out with perfect ease. 
So quickly do they move that the eye can scarcely follow them ; 
one instant a squirrel is in the wheel running with all his might, 
and the next he is seated on a shelf at the opposite end of the 
cage, the wheel whirling behind him. They rarely check the 
speed of the wheel when wishing to leap out, but when it is in 
motion and one wishes to enter it, he often clings to one of the 
spokes and as he is borne around, sidles in. When, as in summer 
often occurs, the wheél is kept in motion at full speed for nine or 
ten hours, with very little rest, the distance which the squirrels 
have travelled is not inconsiderable, being much more than most 
men could perform day after day, and yet they never seem in the 
least weary but are ready at any time for a fresh start. Their 
chief locomotive power resides in the hind pair of legs, which are 
So powerful that the body can easily be held horizontally by them, 
the feet clinging to a wire of the cage as the only support of the 
Whole. In most rodent animals the front legs are comparatively 
weak and are used mainly for holding food, and when the animal is 
running they seem rather to move in response to the pushing force 
of the hind legs than to aid very much in propelling the body. 
They usually move about the cage or room, or in the wheel, by run- 
ning as other animals would, but sometimes they change this for a 
series of short leaps, or leaps which again may change into bounds 
of considerable length ; and very graceful are these latter, so light 
and easy do they appear. Indeed, it is impossible for them to be 
awkward or clumsy in any of their movements. Though usually 
very quiet they are not always displeased with noise, if it be a 
lively one; for instance, they drop a nut in the wheel and then as 
it rattles when the wheel moves they are highly delighted, some- 
times more so than some of the other listeners. Once w 
butternut thus became quite a trouble to me I removed it, but no 
sooner had I left the cage than they put it back and set it rattling : 
louder than ever, leaping over it as it came near them and jumping 
about as if performing a war dance, and this they repeated over 
and over again till, finally, the nut was removed from the cage. __ 
Now and then the freak takes one or the other to leave the wheel __ 
altogether for several days, and in the meantime they relieve their 
Over-buoyant feelings by executing a brilliant series of somer- : 
