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house on the concrete floor in metal boxes. Pupae kept in 

 this house are usually a week later in emerging in the spring 

 than the normal, as they get the frost but no sun, and the 

 concrete floor is 3 ft. below the surface of the ground. 



I obtained some 40 fine pupae, and as all are now alive 

 (March 1) and show no signs of forming up I think I may 

 claim that I have proved that P. atalanla can pass the winter 

 in the pupal stage. 



This discovery appears of great importance, and to me 

 seems to throw a new light on the life-history of this common 

 butterfly in England. 



As many of you know, I have proved to my own satisfac- 

 tion, but not to some others, that P. atalanta cannot pass the 

 winter in England as an imago. I have for the past 10 years 

 experimented with the species, and the only way in which I 

 can carry it successfully through the winter is by feeding it 

 regularly. I grant several records are to hand of the imago 

 being found alive in January and February, among them are 

 the records of my friend Mr. Walter Barnes, and his observa- 

 tions are thoroughly to be relied upon; but this finding of 

 an odd specimen or two over long periods of years does not 

 prove to me that the species can hybernate in England, there 

 is no record that these January and February specimens live 

 till April or May and pair and carry on the race. We all 

 know that in mild autumns and winters we can find wild 

 larvae and pupae in November and December, and we usually 

 bring these into a warm room and breed out the imagines in 

 December or January. Now why should not these found 

 specimens be very late natural emergences ? Say January 

 ones, and that being the case they would live for a few weeks 

 without food, tucked securely away among creepers or ivy, 

 but would die oft" before the spring. We have many of us 

 seen or captured in April or early May absolutely perfect 

 specimens which look as if just out of the pupae, and we have 

 wondered how they can look thus if they are hybernated 

 specimens or immigrants. My discovery that the species 

 can pass the winter in the pupal stage seems to clear up the 

 mystery of these fresh spring specimens. 



I wish it clearly understood that I am still of the opinion 



