THE YOUNG NATURALIST. 



63 



morphos, and having the band across the upper wing curved, and the 

 underwing band swept outwards at the angle of the wing, forming an heraldic 

 shield when the insect is well set ; feeds on Salix fusca on sand-hills. 

 Next we have the moor or moss fed species, B. roboris of Std., deep 

 richer brown, still hardly ever having any indication of a shoulder patch. 

 Sometimes without band on the underwings, often only a faint line on both 

 male and female ; it is in this group that intermediate varieties occur, where 

 the male coloration sometimes approaches the female and that of the female 

 sometimes assimilates to male colorisation. It is in this group also that the 

 scaleless specimen occur most freely, but that, I only name incidentally, it has 

 nothing to do with the question before us. Variety are those intermediate 

 forms when male and female of a species differ. 



I will give another home illustration, which cannot be controverted, 

 Satumia Carpini, I possess several intermediate specimens of females 

 having almost male colouring, the only light grey upon them being the 

 " white of the eye," as seen in the upper wing of the male, which gives the 

 exact representation of the human eye ; but I may be met again with 

 the remark, " Yes, but you don't tell us how many specimens you bred 

 before you got these together." To that I say, all the specimens ever bred 

 or captured, either of Carpini or Betularia, are a mere dot as compared 

 to the number developed naturally, hence the doubt about their fewness 

 proves nothing, but the fact that one puny collector can breed or capture 

 several specimens proves that there are great numbers at large. Again, 

 Didymata has distinct male and female forms, and intermediate forms are 

 plentiful, some females approaching the male, and some males approaching 

 the female. Some, nay most females here, are dark, whilst at Windermere 

 they are all much lighter, and those brought from Hoy, by Mr. Curzon are 

 almost white. But leaving the British Isles let us go to Germany to V. Levana, 



Vanessa prorsa is a large species (comparatively), very dark, with a 

 white band across the wing, like a miniature Liminitis sybilla, 



V. levana, spring form of the above, is rather like a miniature C-album 

 in colour ; no white band ; and 



V. Parina is quite as large if not larger than Prorsa, but not so dark, 

 and the white broken band has become reddish-yellow. 



These are the three broods of Vanessa prorsa — spring, summer, 

 and autumn. Surely one of these three is an intermediate variety. I 

 quite agree with Mr. Eobson that it would be well to know the causes 

 of variation in general, and I think a good deal can be done to elucidate 

 it, but I am no inductive philosopher or speculative theoriser — I am 

 merely a practical naturalist, and give these illustrative facts, leaving to others 



