216 Annals Eyitomological Society of America [Vol. XII, 



quarters in connection with other plants. However, Nelumbo 

 often occurs somewhat remote from shore and while, as will be 

 shown later, these larvae are efficient swimmers, it seems rather 

 doubtful if such is the only method. Since pupae are found in 

 the upper end of the Nelumbo petioles during the summer, the 

 writer is inclined to suspect that hibernation, in the aquatic 

 situations, may occur as pupae in cocoons within the old food 

 plants. Circumstantial evidence also seems to indicate more 

 than one generation per year. During the first week in July, 

 larvae of all sizes as well as pupae were found and from that 

 time to early August, when the writer's observations ceased, 

 adults were emerging continually from the Nelumbo petioles. 

 Quite a number of such pupas were reared in aquaria in the 

 laboratory. Since these immature forms occurred in connection 

 with the fresh leaves and petioles and were of all sizes and ages, 

 the evidence seems clear that they were not overwintering 

 individuals. Furthermore, the emergence of adults throughout 

 the most of July (and possibly to some extent later) and the 

 finding of eggs on July 28th, suggests a midsummer brood. 

 Therefore, the writer is inclined to believe that in the region 

 of Lake Erie' the species is at least double-brooded and that 

 hibernation rttay occur in connection with the aiquaitic food- 

 plants. ;.;;--.-. ..-._,:.; ■ ■: < ' - ■ - • :- ' l 



ADAPTATIONS TO AQUATIC SURROUNDINGS. . =,. 



The chief aquatic adaptations manifested in this species are 

 related to the problems df food-getting, locomotion, and 

 respiration — problems which are always of vital importance in 

 the adjustment of an animal of terrestrial origin and organiza- 

 tion to partial or complete aquatic life. While this species 

 thrives under the conditions of its aquatic surroundings, it is 

 interesting to note that the complete, original terrestrial 

 organization has apparently been retained, that no structural 

 features of aquatic importance have appeared, and that the 

 adjustments to the water are very largely, if not entirely, 

 physiological, consisting of habits and activities which result 

 in the favorable solution of the problems involved. The 

 physiological adjustments of this species to water offer a 

 very close and interesting parallel to those of Bellura melanopyga 

 Grote (Welch, 1914) a species which is remote from Pyrausta 

 penitalis in kinship, but which has solved its major problems 



