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LIFE HISTORY. 



Recapitulating the facts brought out in the various articles cited 

 above, the life history of the leaf crumpler may be briefly given 

 as follows: The small, grayish moths appear in June or July, 

 and deposit eggs on the various trees which serve as food plants 

 for the larvae. From these eggs there soon hatch small brownish 

 worms, which construct tubular silken cases, within which they 

 remain concealed when not eating. As they grow larger they 

 draw about the openings of their abodes many partially eaten 

 leaves, so that by autumn there is quite a bunch about each case. 



At the approach of cold weather the cases are attached to the 

 twigs by means of silken threads, the larvae frequently gnawing 

 away the tender bark to insure a firm hold; and thus the winter 

 is passed. As soon in spring as the leaves begin to appear the 

 larvae attack them, frequently eating out the flower buds as well. 

 They continue feeding and growing until some time in June, when 

 they become pupae. Professor Garman found both larvae and pupae 

 at Champaign June 13, 1885. About a fortnight later the moths 

 emerge, and thus the life cycle is completed. In the breeding- 

 cages of the laboratory the moths have emerged as early as June 

 22 and as late as July 24. 



From the references ^iven above, and the note-slips of the office, 

 it appears that the leaf crumpler feeds habitually upon the apple, 

 quince, and possibly the peach, and on both the wild and culti- 

 vated varieties of the cherry, plum, and crab-apple. 



INTRODUCTION INTO NEW LOCALITIES. 



I know of no other orchard insect that is so liable to be generally 

 introduced into new localities through the dissemination of young 

 fruit trees as this, the peculiar winter habit of the species being 

 such that, unless the trees are examined with special reference to it 

 before they are sent out, a few of the larvae are almost certain to 

 adhere to them. Hence, both the yjerson sending and the one re- 

 ceivii]g young fruit trees should be careful to pick off and destroy 

 all suspicious looking leaf-masses. It may be argued that this pest 

 is so generally distributed that it would make no difference were 

 a few more to be introduced into each locality every year; but it 

 does make a difference, for the balance which nature has adjusted 

 between these insects and their various enemies is thus disturbed, 

 and a new energy is infused ^nto the work of destruction. 



PARASITES. 



Besides the parasites mentioned above by Dr. LeBaron and 

 others, we have bred from this species an undescribed chalcid 

 belonging to the genus Eupelmus. 



