The Saw-Flies 



for its first meal after each molt. When full grown it molts a 

 fifth time, leaving its cast skin as a slender line of slime attached 

 to the leaf. It now appears as a light orange-yellow worm, 

 perfectly clean and dry, with no slime. It then crawls down the 

 plant to the ground, penetrating for half an inch or more and 



forming a little cell the sides of 

 which it moistens with saliva, thus 

 forming a kind of cocoon of firm tex- 

 ture, more or less impervious to water. 

 Near Washington the first gen- 

 eration of larvae leaves the trees by 

 the end of June, and a second genera- 

 tion begins to appear soon after; but 

 in New York State many of the in- 

 dividuals of the first generation pass 

 the winter in their cocoons. The insect hibernates below the 

 surface of the ground, and the flies appear the following April 

 or May. 



No insect is easier to destroy than the pear slug. All of the 

 insecticide mixtures kill it readily, and even throwing dust over 

 the leaves will destroy it. 



Fig. 50. — Pear Slug: a, cocoon; 

 *, contracted lar\'a; ^, pupa — 

 all enlarged. (After Marlatt.) 



