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animals which prey upon caterpillars, as birds, lizards or small mammals, not 

 even to mention insects of prey. And, moreover, man perceives his error as 

 soon as he examines the animal accurately and closely, or with a magnifying- 

 glass; the former is also done by those animals as the sharp sight of the 

 birds answers also pretty well to the latter. 



A calm examination, indeed, which does not proceed from preconceived 

 ideas about mimicry, but which follows from the observation of facts, leads here 

 also to another view. When we compare the caterpillar mentioned here with other 

 caterpillars which also show a strong so-called snake-mimicry, viz. with several 

 larvae of Sphingidae, we see that with these the mimicry is caused because 

 the caterpillar, when frightened, draws in its head and its two foremost segments 

 into the two next ones. Now these two — the 3'^'^ thoracic and the i^' abdominal 

 segment^ are in these species much thicker than the other body-rings; moreover, 

 they have in each side a large eye-like spot, so that the caterpillar in drawing 

 in the forepart of the body looks blunt and very thick, and by the apparent 

 eye on both sides, like the head of a snake. This drawing in of the head to 

 protect it, as other larvae do also, is thus the principal factor in this pheno- 

 menon, as has been rightly observed also by PouLroN and by Meluola. We 

 can readily admit now that the getting thicker of the two above-mentioned 

 segments will simply be the result of it, viz. a formation which serves to 

 advance this drawing in and the protection aimed at by it ; perhaps caused 

 by a special development of the muscles which serve this purpose. With this 

 getting thicker of these rings, the ocellated spot may also have got larger; 

 the same spot is still found also, but less developed, on the sides of the other 

 segments that have not become thicker. In this way this seemingly mimetic 

 formation may have originated without any selective doing or mimetic meaning 

 or design. Now the body of the caterpillar of I. Glaucippe L. there where 

 the two last thoracic segments are, is much thicker than elsewhere, which causes 

 the same effect, while the apparent eyes are formed by two bumps on each 

 side, which are nothing but such eminences as those composing the lines on 

 each side, but which in consequence of the getting thicker in that place are 

 also more developed than in other places. So it is very probable that a 

 similar origin may just as well be attributed to the so-called mimicry in this 

 species, as to that of the above-mentioned larvae of Sphingidae, in which the 

 thickering owing to a more or less different cause has taken place also in a 

 somewhat other way. 



The chrysalis has no projections, but is very much bent; in this respect 

 it closely resembles the pupae of the genus Terias. It is of a dirty yellow 

 or green colour; a few days before the emerging of the imago, its red spots 



