l60 . THE INSECT WORLD. 



optical illusion which imparts to the robe of the chrysalis the golden 

 hues of a princess in grand costume. All is not gold that glitters, 

 Reaumur proves literally, in the case of chrysalis.* 



Let us add that the chrysalis remains thus superbly dressed as 

 long as it is tenanted, but loses its colour as soon as the butterfly 

 has quitted it. 



The cone-shaped pupae belong to the twilight and night-flying 

 Lepidoptera, and to those butterflies whose caterpillars are onisci- 

 form, or in shape resembling a wood-louse. They are generally oval, 

 rounded at the head, and more or less conical at the lower end. 

 Their colour is*generally of a uniform chestnut brown. 



What a mystery is that which is accomplished in the transition 

 from the chrysalis to the perfect state ! Those great changes from 

 the larva state to that of the pupa, and from the pupa to that of the 

 imago, are accomplished with such rapidity, that the phenomena 

 were looked on as sudden metamorphoses, like those related in 

 mythology. It has been thought also that there was in these changes 

 from one state to another a sort of resurrection. There is here 

 neither sudden metamorphosis, nor, as we will show, resurrection. 

 In fact, the chrysalis is a living being ; it indeed shows its vitality by 

 exterior movements. Under the old skin of a caterpillar about to 

 moult, under the envelope which is soon to be cast off, the new 

 integuments are being prepared. 



Some days before the moult, split the caterpillar's skin, and you 

 will find the skin which is to take its place already beneath. If, 

 some days before the transformation of the caterpillar into a chrysalis, 

 it is dissected, the rudiments of wings and antennae may be dis- 

 covered. If a chrysalis is examined on the outside, all the parts ol 

 the future insect can be distinguished under the skin : the wings, the 

 legs, the antennae, the proboscis, &c. ; only, these parts are folded 

 and packed away in such a manner that the chrysalis can make no 

 use of them. It could not, moreover, make use of them on account 

 of their incomplete development. Fig. 127 shows, after Re'aumur.l 

 a chrysalis magnified and seen from its lower side, on which wt 

 observe : — a, the wings ; b b, the antennae ; /, the trunk or proboscis. 



There is a moment when these parts, pressed one against eacl 

 other, and as it were swathed up like a mummy, are very easily seen 

 for they are, as we may say, laid bare. This moment is that ir 



* The word is derived from XP'I'^^^, golden ; for that reason pupa is a bette 

 word than chrysalis, as this only strictly applies to a very small number ; for thi 

 same reason aurelia is a bad word. — Ed. 



t Tome i., p. 382, planche 26, Fig. 6. 



