889 



pattcni as on the Caterpillar. The pupae of Tlc/jialus Inpulinui< 

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

 ranged, in my opinion, as in type I, augmented by s. dorsolateralis. 



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

 pnpal pattern, consisting of setae which had accumulations of 

 pigment at their bases. 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 jjroof of the theory, 

 that the pupa is a subimaginal stage which has secondarily become 

 immovable. Consequently the pupa is not a phylogenetically younger 

 form, but a preserved primitive form which has l)ecome secon- 

 darily immovable. The agreement between the pattern of the 

 Caterpillar instar I and the pupa is so striking, and the diflferences 

 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 different ways. Deegener (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 bidden 

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

 returns, to be sometimes overspread by a homogeneous' colour. 



Even on the imagines (J. F. van Bemmelen, 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 Stadiën in den folgenden Gene- 



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