850 



that the above mentioned general supposition, as well as the rules 

 about colour-design connected with it, may be applied to all groups 

 of Lepidoptera; the undersides of Heterocera- wings showing a far 

 greater fundamental similarity in design than could possibly be con- 

 cluded from the far more altered condition of the upper surface, 

 where the contrast between fore- and hindwing is usually very sharp. 



Evidently the detailed com|)arison of all existing liepidoptera- 

 patterns must be claimed as a condition for such a general inference, 

 but at the same time it may be asserted, that its probability increases 

 with every new group, for which its applicability can be proved. 

 On this account I consider the special inspection of small and sharply- 

 limited families highly important, and think this should precede a 

 general survey of the whole order, as given by de Mkyere, in which 

 necessarily each family can be examined only cursorily and super- 

 ficially. 



That I have chosen Arctiïdae this time, is to a certain point a 

 matter of accidental predilection, Sphingidae or Noctuïdae being 

 [)robably as suitable as a starting point, Geometridae even more so. 



Partly my choice may be juslitied by the vivid colours and the 

 seemingly fantastic markings which characterise many members of 

 this family and by which probably also de Meyere has been moved 

 to mention the Arctiïdae in the very beginning of his paragraph 

 on Lepidoptera as an uncommonly cleai' and complete instance of 

 the «iispersal of spots, in connection with the system of longitudinal 

 wingveins, and frequently to choose his examples from this family 

 in the course of his treatise. 



Arctia caja may serve as a fit starting point, especially so because 

 on the superior wingsurface of this form the contrast between fore- 

 and hindwing is particularly strong, in regard as well to the pattern 

 as to the hues, displayed in its composition. The forewing shows an 

 apparently hizari-e marmoration in creamy white and darkbrown, 

 the hind one a group of five black blotches, with a lustrous blue 

 centi-e and a thin yellow outer circle, arranged on a background 

 of crimson. 



This same contrast in pattern and hues between fore- and hind- 

 wings may be retraced in several congeneric species, but with many 

 modifications, which in my opinion are very instructive. Though I 

 do not propose in this paper to consider the colours as such, I wish 

 to remark, that red is often replaced by yellow, brown by black. 

 The creamy white may rise to deep jellow, the blue lustre on the 

 black markings of the hindwings may be absent, as also their yellow 

 lining. Lastly the contrast between light and dark hues may almost 



