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(Mtterii as on the caterpillar. The pupae of Hepialns lupuUntua 

 in the coll. Kali, are a little damaged, yet they show setae ar- 

 ranged, in my opinion, as in type I, augmented by ». dorsolateralin. 



It seems to me, that these are remnants of a formerly common 

 pupal |>attern, consisting of setae which had accumulations of 

 pigment at their baM>s. Just as is the case with the caterpillars, 

 the pigment spots can remain after the disappearance of the setae. 

 I cannot but think that this pattern of the pupae has taken origin 

 on a movable animal. Therefore I believe that I am allowed to 

 consider these remains of a pupal pattern as a proof of the theory, 

 that the pupa is a subimaginal stage which has secondarily become 

 immovable. ConstMjuently the pu|>a is not a phylogenetically younger 

 form, but a preserve*! primitive form which has become secon- 

 darily immovable. The agreement between the pattern of the 

 caterpillar instar / and the pupa is so striking, and the differences 

 between the pattern of the last larval instar and the pupa 

 are often so considerable, that it becomes interesting to try to 

 solve this problem. 



I believe that this can only be explained by accepting the 

 first larval instar as well as the pupa as primitive forms, but 

 the following instars as newly acquired ones. The latter instars 

 are all specialized in diflFerent ways. Dekoener (1909) has also 

 advocated this hypothesis. Some instars become bearers of 

 warning colours, others obtain long thick tussocks, a third group 

 retains the primitive type pretty well, because it lives in hidden 

 places, but, when the pupal stage has begun, the old pattern 

 returns, to be sonietimes overspread by a homogeneous colour. 



Even on the imagines (J. F. van Bemmelex, 1912) the old 

 pattern is sometimes to be seen. W. Muller (1886) thought that 

 the pattern could pass from the caterpillar on to the pupa, and 

 also the other way about. I think I have proved by the detailed 

 account of the Pierids, that in this case it certainly cannot be 

 true. Therefore we must return to the opinion of Weismann 

 (1876), who concluded from all these phenomena: "dass die 

 Errungenschaften der einzelnen Stadien in den folgenden Gene- 



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