NOTES ON COLLECTING. 95 



have disappeared in those particular localities. It seems then, there 

 can be no real doubt that these beautiful pale-coloured forms, whether 

 white, or completely suffused with grey, or of any intermediate form, 

 are only aberrations of bryoniae ; indeed it is to me impossible to see 

 how their origin could otherwise be satisfactorily explained. 



Having once come to this conclusion, these pale aberrations become 

 objects of the greatest interest. Writing of bryoniae, Kirby, in his 

 " Butterflies of Europe," says : " Some writers consider that this 

 butterfly is a survivor of the Glacial Epoch, and that bryoniae represents 

 the form of the species which was then in existence." There is ample 

 support for this theory if one considers some of the features of the 

 European races of napi. "We see, for example, the specialised under- 

 side of the spring and summer broods ; the universal white 2 ; the 

 very distinct Irish raGe, with its strong tendency to narrower and more 

 elongated wings, the deeper coloration not infrequently seen on the 

 underside of the $ s, the frequent appearance of a yellowish ground 

 colour on the upperside in the same, and the occasional bryoniae-\ike 

 specimens, which also occur rarely elsewhere in the lowlands. All 

 these (excepting the aberrational bryoniae) independently developed 

 features are characteristic of, and typical in, their own sphere and 

 their own season ; yet, a fair series of bryoniae taken in one locality 

 can produce individuals of each form flying together at the same time, 

 and without doubt often hatched from the same batch of eggs. 



The co-existence of all these characteristics in one race and that 

 race the one indigenous in the Arctic and Alpine regions is so 

 suggestive, that one may say for certain that a cold-loving bryoniae 

 form existed everywhere in the lowlands of Europe at the close of the 

 last Glacial Epoch. The great interest attaching to the pale aberra- 

 tions of bryoniae will now at once become apparent. Existing 

 aberration ally in those days in the plains, as they now do in the Alps, 

 and favoured by the changing climatic conditions, they increased and 

 developed. Who can doubt that we seethe result to-day, and that the 

 universally distributed ? napi of the~ lowlands originated in this 

 manner ? 



When in the future, a collector has the good fortune to take one 

 of these beautiful aberrations of bryoniae, instead of designating it a 

 hybrid between two insects which almost certainly do not inhabit the 

 same plain of altitude, he will know it to be but a simple aberration. 

 But that humble prefix will be to all who use it, a direct reminder of 

 the origin and true significance of these white or slate-coloured 

 bryoniae ; which in themselves are an unfailing testimony to the 

 existence and activity in the present day, of that fundamental but un- 

 definable energy which in past ages responded to the changing 

 circumstances and gave rise to a new race of insects, to replace the 

 disappearing type. And so these aberrations are, and will remain, not 

 only for us, but for generations of Entomologists yet to come, a living 

 memorial to the changes of the far past. 



Jg^OTES ON COLLECTING, Etc. 



Gavarnie Notes. — Addenda. — Beferring to my notes on Gavarnie, 

 etc., in the January number of the llecord, Mr. B. C. S. Warren has 

 very kindly gone through my black and white skippers and the result 



