MEANS OF DEFENCE OF INSECTS. 405 



could not discover the sliijhtest trace of any other insect or substance on 

 which it could by possibility feed, but apparently passing a life of absolute 

 solitude in the midst of these burning sand^) had the most perfect identity 

 of colour with that of the soil on which they were found, being brown where 

 the soil was brown, and at not above a hundred paces distant of a silvery 

 white, when found amongst the white particles of broken shells or calca- 

 reous rocks of a similar dazzling colour. That it was the same species 

 which exhibited this change of colour, M. Lefebvre did not doubt, nor 

 that the object was its protection from its enemies, which it was so well 

 calculated to effect that he could scarcely detect it by the closest inspec- 

 tion ; but he confesses himself unable to explain whether the different 

 coloured Eremiaphilce were confined to the soils of the same tints re- 

 spectively, or, as in the case ofthe birds and quadrupeds which become 

 white in winter in the Polar regions, they have the faculty of changing their 

 colour as they change their abode.^ 



Many insects, also, are like pebbles and stones, both rough and polished, 

 and of various colours ; but since this resemblance sometimes results from 

 their attitudes, I shall enlarge upon it under my second head: whether, 

 however, it be merely passive, or combined with action, we may safely re- 

 gard it as given to enable them to elude the vigilance of their enemies. 



A numerous host of our httle animals escape from birds and other as- 

 sailants by imitating the colour of the plants, or parts of them, which they 

 inhabit ; or the twigs of shrubs or trees, their foliage, flowers, and fruit. 

 Many ofthe mottled moths, which take their station of diurnal repose on 

 the north side ofthe trunks of trees, are with difficulty distinguished from 

 the gray and green lichens that cover them. Of this kind are Aliselia apri- 

 lina and Acronyda Psi. The caterpillar of Bryophila A/gce, when it feeds 

 on the yellow Lichen juniperinus, is always yellow ; but when upon the 

 gray Lichen saxatilis its hue becomes gray.'* This change is probably pro- 

 duced by the colour of its food. Leptocerm atratus, a kind of May-fly, 

 frequents the black flower-si)ikes of the common sedge {Carex riparia), 

 which fringes the banks of our rivers. I have often been unable to dis- 

 tinguish it from them, and the birds probably often make the same mistake 

 and pass it by. A jumping bug, very similar to one figured by Schellen- 

 berg *, also much resembles the lichens of the oak on which I took it. 



The spectre tribe (Phasma) go still further in this mimicry, representing 

 a small branch with its spray. I have one from Brazil eight inches long, 

 that, unless it was seen to move, could scarcely be conceived to be any 

 thing else ; the legs, as well as the head, having their little snags and 

 knobs, so that no imitation can be more accurate. Perhaps this may be 

 the species mentioned by Molina*, which the natives of Chili call " The 

 Devil's Horse."" 



Other insects, of various tribes, represent the leaves of plants, living, 

 decaying, and dead ; some in their colour, and some both in their colour 

 and shape. The caterpillar of a moth {Iladcna Ligustri) that feeds upon 

 the privet is so exactly of the colour of the underside of the leaf, upon 



1 Ann. Soc. Ent. de France, iv. 455. 



3 Fabr. Vorlesungen, 321. 5 Cimic. Helvet. t. iii. f. 3. 



4 Hist, of Oiili, i. 172. 



5 Since the first edition of this volume was printed, a lady from the West Indies, 

 looking at my cabinet, upon being shown this insect, exclaimed, " Oh, that is The 

 iJevWs Horse I " 



DD 3 



