( lxiii ) 



fluttering in the cage, were perfect specimens, several indeed 

 might be called' beautiful. 



The reason why these pale spring forms are, all but two, 

 ahead of the wild ones is because they were treated exactly 

 the same as the last year's dark spring forms, or some of 

 these. The pupae were exposed in their cage to the outside 

 air in an eastern aspect during the (comparatively) severe 

 weather of the past winter, but on February 18th four were 

 brought into my study, where there was the usual tempera- 

 ture of a room heated through the day from an open fireplace. 

 These four produced butterflies on the 6th, 8th (2) and 9th of 

 -March, all being males. The rest of the pupae were brought 

 indoors about March 7, some already showing slight signs of 

 approaching emergence, and the butterflies appeared from 

 March 23rd to April 8th. Counting the crippled example, 

 above alluded to, six in all were females. Although I have 

 no specimens of my previous captures or bred examples for 

 comparison, it seems clear to me that this bred series belongs 

 to what I have called the " early " or " pale " spring form 

 of ciir rides, and that my supposition, that this form must be 

 the produce of over-wintered pupae, is correct. 



There is, however, still one point in connection with the 

 spring butterflies that I have not alluded to. Even earlier 

 than the " pale spring form " in several years I have noticed, 

 as a rare occurrence, the appearance of casual dark specimens, 

 that look quite out of place amongst these more conspicuously 

 spotted ones. A dark example of this sort I caught in a 

 lane near my house on March 24th this year, and a tattered 

 specimen, that must have been out for a week, at the beginning 

 of April. The first wild specimens of the " pale " spring form 

 were seen (several in half an hour) on April 5th, and these 

 quite resembled my bred series. The occurrence of the very 

 early dark butterfly is, I believe, to be explained in this way. 

 In some seasons I have every reason to believe that some of 

 the pupae that would normally result in a second brood fail 

 to do so, and remain over till the following spring and then 

 produce these dark butterflies, which much resemble some 

 males of the 2nd or summer generation. One year, pupae 

 that were obtained by me in July from spring butterflies had 



