572 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



females are wingless and at the first glance look much more like 

 spiders than moths. They are about one-third inch long, of a dull 

 brown or grayish color with a dark brown stripe down the middle 

 of the back. 



Life History. The moths emerge from the pupae in the ground 

 in March and April and the females climb up the trunks of the 

 trees, where they place their eggs in irregular masses of about 

 fifty, under loose scales of bark, in cracks in the bark, in crotches 

 of limbs, etc. The individual eggs are yellowish-green, turning 

 quite dark just before the larva: hatch, of an oval shape, and 

 about one-thirty-fifth inch long. The eggs hatch in about a 



FIG. 426. Eggs of spring canker worm twice natural size. (After W. E. 



Britton.) 



month and the young caterpillars commence to feed on the leaves 

 just as they are expanding, at first eating small holes through 

 them, but later devouring all but the midribs. The young cater- 

 pillars have a habit of dropping from the trees and hanging- 

 suspended on strands of silk. In four or five weeks they have 

 become full grown and enter the soil to a depth of 2 to 5 inches, 

 where they hollow out earthen cells, w r hich they line with a little 

 silk and in them change to pupae, in which stage the summer and 

 winter is passed. The pupa is nearly one-third inch long, light 

 brown in color, somewhat pitted, and the male pupa bears a 

 simple spine at the tip of the abdomen. 



The Fall Canker Worm * 



The Fall Canker Worm seems to be the more common form in 

 New England according to Dr. Britton and is a more northern 

 species according to Coquillet, occurring through the North- 



* Alsophila pometaria Harris. Family Geometridce. 



