SQUIRRELS, GOOD AND BAD 127 
or the hollow left by a rotting root, and extend- 
_ ing it into various connecting chambers. In 
the evergreen forests of: northern New Eng- 
land and Canada, however, he often constructs 
a winter nest among the dense foliage of a 
spruce or cedar, which is a marvel of work- 
manship. ‘‘When  convenient,’’ to quote 
Cram’s account of those familiar to him, ‘‘he 
chooses the nest of some large bird for a foun- 
dation, and in this builds a structure of moss, 
bark, pine-needles, and dead leaves, with walls 
several inches in thickness, and a soft nest of 
dry grass and feathers inside. The bark used 
is of two sorts, the rough outer bark of dif- 
ferent trees broken into small pieces, and what 
appears to be the inner bark of the red cedar, 
torn into narrow strips or ribbons to bind the 
whole together. It is put- together with re- 
markable solidity, and usually freezes hard 
early in the winter, furnishing a thorough de- 
fense against the cold or any other enemy from 
without. The narrow opening at one side is 
provided with a hanging curtain.”’ 
These tree-houses are, however, abandoned 
in the spring, when they become soaked with 
