144 Bulletin of the Brooklyn Entomological Society Vol. XV 



noted a windy day with occasional clouds, direction of the wind 

 not observed. 



Of Parshley's three experiences^ two were in midsummer and 

 the other in June. Here again the breeze was on-shore with 

 fair weather. In my collecting and Parshley's one less obvious 

 fact appears : that the bugs were found in the afternoon. 



Of course, the imagining of explanations for natural phenom- 

 ena is a pleasing intellectual effort; and the explanation may or 

 may not be true. In the present case we have eight factors. 



1. On-shore wind. 



2. Preceding fair, warm weather. • 



3. Bright sunshine. 



4. Abundance of insects in the afternoon. 



5. No nuptial flights. 



6. Fair representation of insects but no great abundance of 

 any one species. 



7. Abundant wild vegetation back of the beach (not mentioned 

 in other paper by myself). 



8. Period of arrival at maturity of many species, or at height 

 of number of mature insects. 



Parshley's remark* that at such times "the ocean reflects the 

 sunlight with a pecuHar sparkling brilliancy " seems to me to be 

 the key to the problem. 



On the days under discussion the insects are moved to flight by 

 the warmth of the atmosphere in the afternoon or late morning. 

 These flights must be in the upper air, since the insects are not 

 noticeable as to numbers while in flight. The bugs that travel 

 against the wind go out to sea. Here, they either get tired and 

 fall exhausted into the sea ; or the intense and dazzling reflection 

 of the sun from the ocean surface attracts them. The insects 

 perceive it, and phototropism lures them to their doom. They 

 fly toward this dazzling light, and are either exhausted by having 

 to struggle against the wind, or naturally gravitate toward the 

 source of light, there to perish.^ The wind, being on-shore, 



3 1917, " Insects in Beach Drift, I — Hemiptera Heteroptera," Can. Ent., 

 XLIX : 45-48. 



4 Op. cit, 48. 



5 1914, " Phototropism in Heteroptera," this Bulletin, IX : 90-96, J. R. 

 de la Torre Bueno. 



