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sheltered under each scale. The first brood of young hatches about 

 the middle of May. I have seen the eggs hatching at Amherst, 

 Mass., on May 25, while LeBaron has seen them hatching from May 

 10 to May 25, and Dr. Riley as early as April 25. According to 

 LeBaron the first eggs which hatch produce only male insects, while 

 those which hatch last produce only females. The larvae crawl 

 about over the leaves for two or three days and then come to rest 

 and begin feeding. According to the observations of the author 

 above quoted the male larvae settle entirely on the old leaves 

 while the females usually migrate to the tender leaves at the ends of 

 twigs. It would seem that this is not a fixed habit, however, as I 

 have repeatedly watched this insect and have never found this 

 marked difference in the place of settling of the two sexes. Le- 

 Baron attributed the habit, as he observed it, to instinct on the part 

 of the female larvae prompting them to take up their abode on the 

 young leaves which would not drop to the ground before the insects 

 had time to develop and produce young. The male insect requires 

 ten days for the development of its scale while the female requires 

 three weeks. Moreover, as has been said, the males hatch first and 

 are therefore first to begin the formation of their scales. The male 

 develops so much more rapidly than the female that it is mature just 

 at the time the female is accomplishing its second molt, immediately 

 after which copulation takes place. 



It is almost impossible to separate the two broods of this insect, 

 the time of hatching extending over so long a period, for scales in 

 all stages of development can be found at any time during the sum- 

 mer. In fact I am not at all sure that there is not a partial or com- 

 plete third brood even in this latitude. LeBaron discovered that by 

 July the females had completed their development and had com- 

 menced laying eggs. These eggs began hatching by the first of 

 August and continued till the middle of September. These eggs 

 produce the second brood of larvae and the adult females resulting 

 from them produce the eggs which, after remaining in that stage 

 through the winter, hatch into the first brood of the following 

 season. Necessarily, from the protracted season of egg-laying dur- 

 ing the summer the development of the second brood is very irregu- 

 lar and no precise dates can be given. I have, however, seen living 

 3 



