LEPIDOPTERA 



729 



in the wings. The frenulum is wanting, there being instead, as in 



the Saturnioidea, a largely expanded humeral angle of the hind wings. 



But these moths differ from 



the Saturnioidea in having 



cubitus apparently four- 

 branched and in having the 



humeral angle of the hind 



wings strengthened by the de- 

 velopment of some extra veins, 



the humeral veins (Fig. 933 



h. v.). 



The larv£e of the Lasio- 



campidas feed upon the foliage 



of trees, and are frequently 



very destructive. 



The family is a small one, 



less than thirty North Ameri- 

 can species are known; but 



these represent eleven genera. 



Our more common species 



represent three genera : Mala- 



cosoma, which includes the 



tent-caterpillars, and Tolype 



and Epicnaptera, which in- 

 clude the lappet-caterpillars. 

 There are several species of 

 tent -caterpillars in this coun- 

 try. Most of them belong to 

 the Pacific coast; but two are 



common in the East. Of these the most common one is the apple- 

 tree tent-caterpillar, Malacosoma americdna. — This is the insect that 

 builds large webs in apple and wild cherry trees in early spring. 

 Figure 934 represents its transformations. The moth is dull reddish 

 brown, with two transverse whitish or pale yellowish lines on the 

 fore wing. The figure represents a male; the female is somewhat 

 larger. These moths appear early in the simmier. The eggs are soon 

 laid , each female laying all her eggs in a single ring-like cluster about 

 a twig; and here they remain unhatched for about nine months. 

 This cluster is covered with a substance which protects it during the 

 winter. The eggs hatch in early spring, at the time or just before 

 the leaves appear. The larvae that hatch early feed upon the un- 

 opened buds till the leaves expand. The larvae are social, the entire 

 brood that hatch from a cluster of eggs keeping together and building 

 a tent in which they live when not feeding. The figure represents a 

 specimen in our collection. In this case the tent was begun near the 

 cluster of eggs. But usually the larvae soon after hatching migrate 

 down the branch towards the trunk of the tree until a fork of consider- 

 able size is reached before they begin their tent. This is necessary, 

 as the completed tent often measures nearly two feet in length. 



Fig. 933- 



id^ 2d A 



-Wings of Malacosma americana. 



