594 HOMES WITHOUT HANDS. 



places that whole rows of fruit-trees are denuded of their leaves, 

 and covered with the silken webs of the pretty but destructive 

 caterpillars. 



The Beown-tailed Moth is another of the arboreal insects, 

 and spins a web very like that of the gold-tailed inoth, which has 

 already been described. In some seasons it is more numerous 

 than in others, and occasionally seen in vast multitudes. This 

 phenomenon is often observable among insects, as is well known 

 to all practical entomologists, and in more than one instance the 

 caterpillars of the Brown-tailed Moth have been so plentiful as to 

 become a positive pest. 



They are social larvae, and, as they are hatched late in the au- 

 tumn, they spin a joint web, in which they can be secure through- 

 out the winter months. As the brood is mostly numerous, and 

 as two or more broods may unite in forming a common dwelling, 

 their habitation is extremely large, often enveloping several 

 branches, together with their twigs and leaves. Like the nest of 

 the gold-tailed moth, it is divided into chambers, and is externally 

 irregular in form, depending entirely for its shape upon the local- 

 ity in which it is constructed. 



Even in this country it is sometimes plentiful enough to annoy 

 the farmer, who does not like to see his hedgerows disfigured by 

 the silken tents spun by these caterpillars ; but in France it has 

 occurred in such hosts as to entail a serious loss upon the agricul- 

 turist, whole rows of trees having been stripped of their leaves, 

 and the denuded branches covered with the sheets of web in 

 which lay the destroying armies. 



On the accompanying illustration may be seen a number of 

 curious nests, composed of long hexagonal cells set side by side. 

 These are made by several species of a hymenopterous insect be- 

 longing to the genus Icaria, and may be advantageously compared 

 with the central figure in the illustration on page 586. 



These nests, or rather these series of cells, are made after a sin- 

 gular fashion. First, the insect attaches to the branch a foot-stalk 

 composed of the same material as that with which the cells are 

 formed. This foot-stalk, although slender, is very hard, solid, 

 and tough, and can uphold a considerable weight, as is necessary 

 from the manner of constructing the nest. She then makes a cell 

 after the ordinary wasp-fashion, attaching it to the foot-stalk with 



