92 



Journal New York Entomological Society. [v<^'- xxx. 



there is a very close correlation between the development of the insect 

 and its host plant, the goldenrod.' 



The time of hatching of eggs occurs in each region when the golden- 

 rod shoots are four to six inches high. This as seen in Table II begins 

 as early as March 26 in North Carolina and probably occurs gradu- 

 ally later as one moves northward, until as far north and east as 

 Vermont, the average date of hatching is as late as May 20. The 

 length of the larval stage extends over 150 days in North Carolina, 

 81 days in New York and 71 days in Vermont. Similarly the pupal 

 stage is longer in the " warmer " regions, being increased from 24 

 days in Vermont to 51 days in North Carolina. We thus see that the 

 activity of the larvae in Vermont begins late (May 20) and ends early 

 (August 23), covering a period of 95 days; at Ithaca, N. Y., it begins 

 slightly earlier (May 16) than in Vermont and ends slightly later 

 (Sept. 10), covering a period of 117 days; while in North Carolina 

 hatching is much earlier (March 26) and emergence much later (Oc- 

 tober 13), covering a period of 221 days. This not only holds true for 

 this insect but for at least one of its primary parasites, Copidosoma 

 gelechicc, as well. 



These data are in a measure an exception to the theory often applied 

 to insects, that the warmer the climate the more rapid the growth 

 and the greater the number of generations. 



Parasites. 

 An exceptionally high percentage of the individuals of all stages 

 is attacked by hymenopterous parasites and their detailed study would 

 afford a fascinating problem. Hyper-parasites and inquilines are 

 also commonly bred from the galls. In two instances two species of 

 parasites {Copidosoma gelechice and Scambus pterelas) were reared 

 from a single larva. 



