THE INSECT RECORD FOR 1 9OO 



13 



practically no damage was 

 done. It is hardly probable 

 that the causes of disappear- 

 ance were the same as those 

 of the Forest Tent Caterpil- 

 lar, because the life histories 

 of the two insects are so dif- 

 ferent. Parasites were prob- 

 ably in part at least respon- 

 sible in this case. Early in 

 May I saw an Antiopa But- 

 terfly depositing her eggs 

 upon the willow twig shown 

 in Fig. 3. As soon as she 

 flew away I saw a tiny fly 

 running about over the eggs, 

 and watched it as it deposited 

 its own eggs in those of the 

 butterfly. This fly was a 

 parasite ; the eggs it deposit- 

 ed would hatch into little 

 grubs that would develop at 

 the expense of the butterfly eggs, preventing them from hatch- 

 ing. In half an hour the little parasite^ laid her eggs in fifteen 

 of those of the butterfly. 



Another observation upon the enemies of this species seems 

 worth recording. While driving along a country road late in 

 May, I saw a Maryland Yellow-throat carrying an Antiopa 

 Butterfly. The butterfly was dropped by the bird when dis- 

 turbed and is shown in Fig. 4, the pieces broken oft^the wings 

 probably indicating where the bird had caught it. 



The American Tent Caterpillar^ was rather more nu- 

 merous than last year, though not at all abundant. Appar- 

 ently the species is slowly increasing, and it is likely to con- 

 tinue so to do for several years, until it becomes so numerous 

 as to do serious damage. As I wrote in last year's Insect 

 Record, the best time to fight the pest is during these years 



^Since determined by Dr. L. O. Howard to be Telenovius graptce. 

 ^Clisiocampa americana Harris. 



Fig. 3. — Eggs of Antiopa Butterfly 

 on Willow Twig. 



