My life : a record of events and opinions - Wallace-online.org

208 MY LIFEof the whole lepidopterous order.In coloration theyare wonderfully varied. The ground colour is veryfrequently black, on which appear bands, spots, orlarge patches of brilliant colours — pale or goldenyellow, rich crimsons or gorgeous metallic blues andgreens, which colours sometimes spread over nearlythe whole wing surface. Some are thickly speckledwith golden green dots and adorned with large patchesof intense metallic green or azure blue, others aresimply black and white in a great variety of patterns,many very striking and beautiful, while others againhave crimson or golden patches, which when viewedat certain angles change to quite different opalescenthues, unsurpassed by the rarest gems.But it is not this grand development of size andcolour that constitutes the attraction of these insectsto the student of evolution, but the fact that theyexhibit, in a remarkable degree, almost every kind ofvariation, as well as some of the most beautifulexamples of polymorphism and of mimicry. Besidesthese features, the family presents us with examplesof differences of size, form, and colour, characteristicof certain localities, which are among the most singularand mysterious phenomena known to naturalists. Ashort statement of the nature of these phenomenawill be useful to show the great interest of the subject.In all parts of the world there are certainwhich, from a disagreeable smell or taste, areinsectsrarelyattacked or devoured by enemies. Such groups aresaid to be " protected," and they almost always havedistinctive and conspicuous colours. In the MalayArchipelago there are several groups of butterflieswhich have this kind of protection ; and one group—the Euplseas—is coloured black, with rich blueglosses and ornamented with white bands or spots.