Melanippe procellata, and the light variety of Gnophos obscuraria, &c.? Why, on the white and light-coloured soils of the south of England, i.e. chalk and limestone. On the other hand, we find the dark variety of G. obscuraria, and various dark-coloured species, on black peaty soils."[1] A noctuid moth, Agrotis lucernea, not uncommon in Britain, when found on the chalk downs in the Isle of Wight has been thus described: " It rests in chinks on the ground, and is of a soft silky grey colour, and covered with such thick and long scales as to give it a furry appearance. Although abundant enough by night, it requires a long search to find a single specimen by day, so difficult is it to distinguish in its native haunts, the long pale silky hairs resembling exactly the rough surface of the chalk dusted with the darker atoms of the soil above." This moth has also been caught by the same entomologist on the east coast of Scotland, and then thus differently described: "On black rocks, sometimes reeking with moisture, and which were as black as the rocks on which they rested." Mr. Tutt, to whom we are indebted for these notes and observations, ascribes the colouration in each case as due to the action of natural selection. We may at least say in respect to other instances he has adduced that this explanation is not so apparent. Noctua glareosa "is of a pale dove-coloured grey, sometimes tinged with rosy," and with three dark spots. "The Sligo specimens are very white,—Scotch specimens more slaty; the Shetland specimens are of a rich blackish brown colour."
Epunda lichenea "is a mottled greenish grey or greenish ochreous species, which is confined to a few coast districts. The Portland specimens are greenish white; the Teignmouth specimens dark greenish ochreous, mottled with red. The moths from these two localities have quite a different appearance, owing to the different kind of rocks on which they rest at these places." Amphidasys betularia, a Geometrid moth, "as it rests on a trunk in our southern woods, is not at all conspicuous, and looks like a natural splash or scar, or a piece of lichen "; but near our large towns, where there are factories, and where vast quantities of soot are
- ↑ 'Entomologist,' vol. xxvi. p. 355. Mr. Wallace considers that the original colour of butterflies was a greyish or brownish neutral tint (' Darwinism,' p. 274); and the same opinion is held by Dr. Dixey in his study of the phylogeny of the Pierinæ ('Trans. Ent. Soc. Lond.,' 1894, p. 290).
