THE WHITE BORDER OF EUVANESSA ANTIOPA, L. 205 



The White Border of Euvanessa antiopa, L. 



By E. A. COCKAYNE, D.M., F.R.C.P., F.E.S. 



The pioneers of Entomology in this country laid great stress on 

 the frequency with which a white border was found in British antiopa 

 and in the older works the insect is often called the " white border " 

 or " white petticoat." Haworth in discussing their origin says, " to 

 suppose they come from the continent is an idle conjecture, because 

 the English specimens are easily distinguished from all others by the 

 superior whiteness of their borders." A long time has passed since 

 we had an antiopa year, and it is now firmly established that they do 

 come from abroad and are not bred in this country as Haworth 

 believed. 



Continental specimens are stated to have a pale border after 

 hibernation, and almost all entomologists now consider that the white 

 border of British antiopa is merely due to fading. 



Tutt in his British Butterflies, p. 329, says " it was once supposed 

 that the British specimens always had a white, instead of a cream- 

 coloured, border, but this has been quite disproved." 



Verity states that in Europe no specimen emerges from the 

 chrysalis with a white border (Ent. Record, 1916, xxviii., p. 102). 

 Many of the earlier entomologists were very accurate observers, and, I 

 think, if we look at contemporary records, we shall find that we have 

 discarded their conclusions too readily. 



The following passage occurs in Newman's British Butterflies, 

 " William Backhouse, in 1820, saw great numbers strewing the sea- 

 shore at Seaton Carew both in a dead and living state, one of these in 

 his collection has the pale whitish margin to the upperside of the 

 wings so characteristic of our British specimens." In the periodicals 

 of 1872, another year in which antiopa was abundant, there are 

 numbers of records of specimens with white borders captured in 

 August and September in good condition. Many of these must have 

 been caught soon after having emerged from the pupa, and the white- 

 ness of the border cannot have been due to fading. 



It is said that in many cases the white border has been produced 

 artificially, and it will be shown that at least one reputed British 

 specimen is a faked example. But it seems most unlikely that faking 

 would have been resorted to if the majority of British antiopa had not 

 had a genuine white border. 



I will now bring forward some new evidence of a different kind, 

 which, I hope, will convince everyone that the old views were correct 

 and that the modern ones are wrong. In the course of examination of 

 many aberrations of Lepidoptera for scale defects I noticed in the 

 British Museum collection an antiopa in bred condition from France 

 with pale grey nearly transparent border, dull blue spots, and the 

 ground colour a little paler than usual. Under the microscope all the 

 upper and lower scales of the border were seen to be so extremely thin 

 and tightly rolled up as to resemble hairs and to be quite transparent 

 owing to absence of pigment. The blue scales were found to be rolled 

 up or twisted, but the chocolate scales were normal in shape although a 

 little less pigmented than usual. This discovery led me to examine a 

 number of British specimens with the following result. 



December 15th, 1921. 



