65 



litj of life-conditions and externul influeiioes, even more so than the 

 caterpillars, their habits of moving abont and resting, of nourishing 

 and propagating being more varied. 



Both caterpillars and imagines in these respecis surpass the nearly 

 immovable and lethargic pupae. 



De Meyere's views on this topic seem to be the cause, (hat while 

 attaching great importance to (he diiferences between the pattern on 

 the pupal wing-sheaths of nearly related forms, sucii as Euchloe 

 cardamines, Pleris hrassicae, Aporla crataegl, he only pays 

 very slight attention to the facts pointed out by me, viz. the great 

 similarity between (ho pupal designs in several families of Rhopa- 

 locera e. g. Papilionids, Pierids and Nymphalids, a similarity 

 not only far exceeding the resemblance between the wing-patterns 

 of the imagines (hat euierge from those pupae, but also rooting in 

 the nearer connections of this pupal pattern with the primordial and 

 ephemeric design, which appears on the developing wings during 

 the course of the pupal life, and only gives place to the conclusive 

 imaginal pattern in the very last days before the emergence of (he 

 imago. 



These vesdgial markings on the rudiments of the wings hidden 

 in (he pupal slieadis, moreover prove to us that a primordial pa(tern 

 may easily continue i(s exis(ence in concealment; therefore such 

 notions as "sympathetic colouration" or "influence of illumination 

 and surroundings" need not be invoked in order to explain the 

 manifestation of such a pa((ern. 



Though the absence of markings may, in all probability, be con- 

 nected with cojicealed life-habits and with absence of light, it would 

 not do to consider these influences as the direct and unavoidable 

 causes of the deterioration of the pattern. For (he pattei-n is evidently 

 able also (o persis( hidden under the pu|)al sheath, though in some 

 forms it is retained much clearer and more complete than in others, 

 without our being able to find an explanation for (his difference. 



Now what holds good for (he wings inside (he pupal sheaths, 

 will probably also apply (o those sheaths themselves. Taking this 

 inference for granted, we might expect, that also in some of those 

 Lepidoptera, whose pupae conceal themselves in hidden spots, the 

 original colour pattern, on the body as well as on the wings, might 

 have been more or less preserved. 



This turns out to be really the case, as I found when studying 

 the pupae of Chaerocampinae amongst Sj)hingidae, and of several 

 genera of Geometridae. In contrast with the majority of the genera 

 belonging to these families, whose pupae are black, brown, yellow 



5 

 Proceedings Royal Acad. Amsterdam. Vol. XXI. 



