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COLOURS OF ANIMALSerastus) is coloured so exactly like these that it was at firstdescribed as a species of Pieris. None of these four groupsare known to be in any way specially protected, so that theresemblance cannot be due to protective mimicry.In South America we have far more striking cases, for inthe three subfamilies Danainse, Acrseinse, and Heliconiinae, allof which are specially protected, we find identical tints andpatterns reproduced, often in the greatest detail, each peculiartype of coloration being characteristic of distinct geographicalsubdivisions of the continent. Nine very distinct genera areimplicated in these parallel changes Lycorea, Ceratinia,Mechanitis, Ithomia, Melinsea, Tithorea, Acrsea, Heliconius,and Eueides, groups of three or four (or even five) of themappearing together in the same livery in one district, whilein an adjoining district most or all of them undergo a simultaneouschange of coloration or of marking. Thus in thegenera Ithomia, Mechanitis, and Heliconius, we have specieswith yellow apical spots in Guiana, all represented by alliedspecies with white apical spots in South Brazil. In Mechanitis,Melinaea, and Heliconius, and sometimes in Tithorea, thespecies of the Southern Andes (Bolivia and Peru) are characterisedby an orange and black livery, while those of theNorthern Andes (New Granada) are almost always orangeyellowand black. Other changes of a like nature, which itwould be tedious to enumerate, but which are very strikingwhen specimens are examined, occur in species of the samegroups inhabiting these same localities, as well as CentralAmerica and the Antilles. The resemblance thus producedbetween widely different insects is sometimes general, butoften so close and minute that only a critical examination ofstructure can detect the difference between them. Yet allare alike protected by the nauseous secretion which rendersthem unpalatable to birds. 1In another series of genera (Catagramma, Callithea, andAgrias), all belonging to the Nymphalidae, we have the mostvivid blue ground, with broad bands of orange, crimson, or adifferent tint of blue or purple, exactly reproduced in corresponding,yet unrelated species, occurring in the same locality ;1The above cases have now been satisfactorily explained as a modifiedform of mimicry. See Darwinism, pp. 249-257.