THE SMALL ERMINE MOTH. 53 
led through the intricacies of Rosamond’s bower. When 
once these caterpillars have taken possession of a tree, 
they are sure to strip it of its leaves as completely as if 
the foliage had been plucked by hand, It is a very 
curious sight to watch the systematic manner in which 
these troublesome insects set about their work, how they 
send out pioneers which lead the way to new branches, 
either by crawling up to them or by lowering themselves 
to them by means of their silken life-lines, and how soon 
they are followed by their ever hungry companions. 
Perhaps the reader may wonder why the little birds do 
not eat these caterpillars. When they have nearly stripped 
the branch, they are very conspicuous, especially as they 
make their way from bough to bough along their silken 
bridges. Indeed, a proprietor of a garden that was much 
damaged by this moth did once mention the immunity of 
the caterpillars as a proof that any tenderness to small 
birds was misplaced, saying that if the sparrows were 
half as insectivorous as I mentioned, they would long ago 
have eaten all the caterpillars. 
Now, at the first glance, there seemed to be some 
reason in this remark; but a short look at one of the 
damaged trees explained the reason why the sparrows did 
not eat the caterpillars. The birds literally dared not 
approach the insects; for the silken threads which tra- 
versed the branches in all directions were an effectual 
barrier, striking against the wings and terrifying the poor 
birds. We all know that a few threads of fine cotton 
passed from bough to bough of a gooseberry-bush will 
deter any little bird from settling on it; and, in the same 
manner, the silken threads of the caterpillars deter the 
birds from settling on the branches. These threads are 
very elastic, and of marvellous strength, considering their 
tenuity, producing most uncomfortable sensations when 
