THE STORY OF AN ENTOMOLOGIST 



and genial Swiss smiled, shrugged his shoulders and answered: 

 "I wish I knew!" 



I am sure that in those boyhood days I did not appreciate the 

 importance of studying insects from the life history point of view, 

 and not at all from the economic. In fact, although I subse- 

 quently gave my collection to Cornell University, I believe that 

 I made only one observation of any especial interest. It happened 

 in this way: I spent the summer of 1870 or 1871 (I forget which) 

 at my grandfather's in Delhi, Delaware County, New York, and 

 while there collected butterflies, incidentally interesting one or 

 two of the local boys. There I found in some number a white 

 butterfly which I identified in Harris as Pontia oleracea, and 

 Harris stated that its larva fed on cabbage and other cruciferous 

 plants. I took a dozen of these butterflies back with me to Ithaca, 

 where the species had not been found, and traded them with 

 some of the other boys. The next summer I wanted some more 

 for trading purposes, so I wrote to Charley Frost, a Delhi boy, 

 and asked him to send me some, since I knew that they had been 

 very common down there the summer before. To my great sur- 

 prise, he sent me back an entirely diflferent species. It was white 

 like the other, but it had some black spots on the wings. 



Now, as it happens, this incident fixes the date at which the 

 European Cabbage Butterfly (Pieris rupee) reached that part of 

 New York. It had been accidentally imported at Montreal, Can- 

 ada, a few years before, and its rapid spreading over the United 

 States was a matter of much interest to naturalists and to cab- 

 bage-growers. 



This was all written up later by S. H. Scudder in an important 

 paper, and he was able to fix the date of the entry of the species 

 into the lower Catskill regions by this boyhood observation by 

 Charley Frost and myself. So that even small boys sometimes hit 

 upon a good thing. 



[7] 



