ON SOME LEPIDOPTEKOUS LARV^. 87 



pupates in nature in a crevice of the bark of a tree, or under 

 loose bark, but in captivity will use the interior of a bottle- 

 cork, or a short piece of bramble stem, from which it 

 quickly excavates the pith. When several of these hand- 

 some caterpillars are moving about in the breeding-cage, 

 they have a very pretty appearance, and the rustle which 

 they make in traversing the leaves is quite audible. The 

 value of warning colours to the larvse which possess them 

 is obvious when we remember the fact already mentioned, 

 that a slight wound, the merest peck from a bird or bite 

 from a lizard, is in nearly every case fatal to the delicate 

 organism. Hence the mere distastefulness of the larvse does 

 not avail the bitten individual, though it will probably 

 make its enemy more cautious in future attacks ; but the 

 possession of these conspicuous colours, when the bird has 

 learnt to associate them with an unpleasant taste, must 

 save many a larva from a fatal bite. 



The caterpillars of the Large and Small Elephant Moths 

 {Chcerocampa elpenor and Porcellus), with some others of 

 the sphingidse, are remarkable for another kind of protec- 

 tion. C. elpenor has a large dark-brown or occasionally 

 dark-green larva, which usually hides amongst the dead 

 leaves on the lower parts of the stem of the Gi-reat Willow 

 Herb, where it is well guarded by the similarity of its 

 colouring. If the plant is touched, however, the larva in- 

 stantly draws back its head and three first body segments 

 into the two next rings, when the fore part of its body, of 

 course, appears much swollen, and the four enormous eye- 

 spots on these two segments suddenly become most promi- 

 nent, and give the creature a truly alarming appearance. 

 It thus resembles the fore part of a snake, the eye-spots, 

 according to Prof. Poulton, giving the effect of the spec- 

 tacle mark on the cobra's dilated hood. In his book on The 



