NOTES BY THE WAY 155 



rocks. In England the rabbit burrows in the 

 ground to such an extent that in places the earth is 

 honeycombed by them, and the walker steps through 

 the surface into their galleries. Our white-footed 

 mouse has been known to take up his abode in a 

 hornet's nest, furnishing the interior to suit his 

 taste. A few of our birds also avail themselves of 

 the work of others, as the titmouse, the brown 

 creeper, the bluebird, and the house wren. But 

 in every case they refurnish the tenement: the 

 wren carries feathers into the cavity excavated by 

 the woodpeckers, the bluebird carries in fine straws, 

 and the chickadee lays down a fine wool mat upon 

 the floors. When the high-hole occupies the same 

 cavity another year, he deepens and enlarges it: 

 the phoebe-bird, in taking up her old nest, puts in 

 a new lining ; so does the robin ; but cases of reoc- 

 cupancy of an old nest by the last-named birds are 

 rare. 



A BOLD LEAPER 



One reason, doubtless, why squirrels are so bold 

 and reckless in leaping through the trees is, that, if 

 they miss their hold and fall, they sustain no injury. 

 Every species of tree-squirrel seems to be capable 

 of a sort of rudimentary flying, at least of making 

 itself into a parachute, so as to ease or break a fall 

 or a leap from a great height. The so-called flying 

 squirrel does this the most perfectly. It opens its 

 furry vestments, leaps into the air, and sails down 

 the steep incline from the top of one tree to the 

 foot of the next as lightly as a bird. But other 



