440 MEANS OF DEFENCE OF INSECTS. 



the African desert, leading to the Oasis of Bahryah, about four days' jour- 

 ney from the Nile, where he could not discover the slightest trace of any 

 other insect or substance on which it could by possibility feed, but appa- 

 rently passing a life of absolute solitude in the midst of these burning 

 sands,) had the most perfect identity of color with that of the soil on which 

 it was 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 calcareous rocks of a similar dazzling color. 

 That it was the same species which exhibited this change of color, 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 inspection ; but he confesses himself unable to 

 explain whether the different-colored Eremiajjhilcs were confined to the 

 soils of the same tints respectively, or, as in the case of the birds and 

 quadrupeds which become white in winter in the Polar regions, they have 

 the faculty of changing their color as they change their abode. ^ 



Many insects, also, are like pebbles and stones, both rough and pol- 

 ished, and of various colors; but since this resemblance sometimes results 

 from their attitudes, I shall enlarge upon it under my second head: whe- 

 ther, however, it be merely passive, or combined with action, we may 

 safely regard it as given to enable them to elude the vigilance of their 

 enemies. 



A numerous host of our little animals escape from birds and other 

 assailants by imitating the color of the plants, or parts of them, which 

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

 fruit. Many of the mottled moths, which take their station of diurnal 

 repose on the north side of the trunks of trees, are with difficulty distin- 

 guished from the gray and green lichens that cover them. Of this kind 

 are Misclia aprilina and Acronycta Psi. The caterpillar of Bryophila 

 Algce, when it feeds on the yellow Lichen juniper inus, is always yellow ; 

 but when upon the gray Lichen saxitilis its hue becomes gray.^ This 

 change is probably produced by the color of its food. Leptoccrus atra- 

 tus, a kind of May-fly, frequents the black flower-spikes of the common 

 sedge (^Curex riparia), which fringes the banks of our rivers. I have 

 often been unable to distinguish 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 Schellenberg^, 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. 1 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, 



* Ann. Soc. Ent. de Franre, iv. 455. * Fabr. VorJesungen, 321. 



» Cirnk. Helvet. t. iii. f. ?. * Hint, of Chili, 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 Devil's Horse!" 



