114 OCCASIONAL PAPKRS. 



Is it mimicry of Hyale or of any of the Whites ? 

 Do birds devour the yellow specimens while white 

 ones for some cause or other are passed by ? Or on 

 the other hand do birds devour white specimens and 

 leave the yellow ones which are so much in excess 

 of the others ? Is the white variety only a reversion 

 to the original colour ? More questions again for us 

 to puzzle our minds over. 



You may perhaps say that from a bright orange 

 ground colour to a white can hardly be looked on as 

 a gradual change as we see it. Last year's captures 

 have enabled me to reply to this. Mr. Austen 

 showed me a specimen he had taken in which the 

 ground colour was a beautiful light golden yellow ; 

 and it was very doubtful as to whether it ought to be 

 labelled Edusa or Helice. Mr. Blackall has a similar 

 specimen, and I have one lighter still, but not white. 

 I then ventured an opinion that if it were possible 

 to place side by side a very large number of captures of 

 the two forms we should find every tint, from the orange 

 of Edusa suffused with a rosy purple light to the milk 

 white Helice. Such I find was the case at the Ento- 

 mological Exhibition, held in March at the Royal 

 Aquarium. It was absolutely impossible to say where 

 Edusa terminated and Helice began. In the plate of 

 examples on the table you will also notice this. And 

 in addition you will find one specimen having the 

 fore wings of Helice with the hind wings of Edusa ; 

 another again which has both wings on the right side 

 those of Helice, while the left are those of E<1nnu. 

 So you see it is possible to believe in a firadual trans- 

 mutation from one to the other ; but it is impossible 

 to say why the change is limited to the females. 



