154 INSECT TRANSFORMATIONS. 



Albin and Donovan ; but Rosel's figure, which we 

 here copy, is more accurate. 



Looking- at these very sing-ular forms of caterpil- 

 lars, we could not anticipate, without previous know- 

 ledge, that all of them produced insects of nearly the 

 same shape, though differing considerably in size 

 and colour. It is not a little remarkable, also, 

 that the colours of caterpillars, with a few excep- 

 tions, such as the magpie- moth {Abraxas grossula- 

 rlata), are very different indeed from the insects into 

 which they are transformed. Plain and inconspi- 

 cuous caterpillars will sometimes give splendidly co- 

 loured insects, as in the case of the Vanessa butter- 

 flies ; while finely marked caterpillars will give 

 plain insects, as the one whose gaudy stripes of sky- 

 blue, scarlet, and black, has obtained it the appro- 

 priate name of the lackey {Clisiocampa iieustria^ 

 Curtis), though the moth is of a dull brownish 

 yellow. Two of our finest native insects, however, 

 the swallow-tailed butterfly and the emperor-moth, 

 are produced from beautifully coloured caterpillars ; 

 but neither the colours nor the markings of these 

 have any resemblance. 



A more extraordinary difference, however, between 

 the first and the last stage of insect life occurs in the 

 case of those insects whose larvae are aquatic. One 

 of our commonest families of insects, the gnats {Cu- 

 licidfB, Latr.), whose ingenious mode of constructing 

 a floating raft of eggs we have already described, 

 affords a very striking illustration of our position. 

 When these eggs are hatched, the grubs appear; but 

 they do not, as is said by older naturalists, "make them- 

 selves little lodgments of glue, which they fasten to 

 some solid body at the very bottom of the water, unless 

 they meet with chalk, whose softness permits them to 

 burrow into its substance *." On the contrary, they 

 * Spectacle de la Nature, i. 123. 



