200 INSECT LIFE. 



appearance. The male and female of a common spe- 

 cies are represented by Figs. 163 and 164. 



THE LARGER NEST-BUILDING CATERPILLARS. 



Many species of caterpillars make nests within 

 which they live. The greater number of these be- 

 long to the group described below as leaf-rollers a 

 group composed chiefly of very small species. A 

 few of the larger caterpillars also make nests. The 

 more common species of these are the following :- 



THE TENT-CATERPILLARS. See page 172 for a 

 reference to these. 



THE FALL WEB-WORM, Hyphantria cunea (Hy- 

 phan'tri-a cu'nc-a). A very common sight in autumn 

 in all parts of our country is large, ugly webs inclos- 

 ing branches of fruit or forest trees. These webs are 



o 



especially common on apple and on ash. Each web 

 is the residence of a colony of larvas which have 

 hatched from a cluster of eggs laid on a leaf by a 

 snow-white moth. There is a variety of this moth in 

 which the fore wings are thickly studded with dark 

 brown specks. Every gradation exists between this 

 form and those that are spotless. The species win- 

 ters in the pupa state, and the moths emerge during 

 May or June. The webs made by this insect should 

 not be confounded with those made by the apple-tree 

 tent-caterpillar. The webs of the fall web-worm 

 are made in the autumn, and are much lighter in 

 texture, being extended over all of the leaves fed 

 upon by the colony. 



THE SCALLOP-SHELL MOTH, Calocalpa undulata 

 (Cal-o-cal' pa un-du-la'ta).--T\iis is a pretty moth, with 

 its yellow wings crossed by so many fine, zigzag, 



