145 



what is commonly called an " incliworm ; " in both it leaves 

 the tree when through feeding, and changes to the adult moth 

 in the ground ; in both the female moth is without wings ; in 

 both the eggs are laid on the twigs of the trees ; and finally, 

 both the caterpillars feed at the same time of year. Here, 

 however, the resemblance ends. 



#?5^ 



S«5--. 



Fall Canker Worm. 

 The fall canker worm (Alsophila 'pometaria Harr.) ap- 

 pears late in the fall, coming out of the ground; and the 

 wingless females crawl up the trees to the smaller limbs, 

 where the eggs are laid in clusters. In the spring these eggs 

 hatch, producing tiny 

 " inchworms," which 

 feed on the leaves till 

 full grown, this condi- 

 tion being reached in 

 June. They then crawl 

 down the tree or spin 

 down a thread to the ground, where a few inches below the 

 surface they pupate. Here they remain till the approach of 

 cold weather, when the insects, now in the moth stage, leave 

 the ground and pass to the trees to lay the eggs for the gen- 

 eration of the following year. 



:rM. 



^3. 





Fall canker worm: a, male moth; h, female 

 moth; c,d, structural details. 



Spring Canher Worm. 

 In the case of the spring canker worm (Paleacrita vernata 

 Peck.) the moths do not appear in 

 the fall, but during the first warm 

 days in March and April ; and, like 

 the others, the females crawl up the 

 trees to lay their eggs on the twigs, 

 and it is possible that a cluster of 

 freshly laid eggs of the spring 

 canker worm may be placed close 

 beside a cluster of eggs of the fall 



Spring canker worm: a, fuU- 

 grown caterpillar; b, en- 

 larged egg, and part of a 

 mass, natural size; c, d, 

 structural details. 



canker worm which have been there all winter. 



The eggs 



