As a further example, I now select a diurnal butterfly from Africa, _Papilio merope_ Cramer[3], which was shown by Trimen in 1868 to be mimetic. The species has a wide distribution, for, if we except slight local differences in the marking of the male, its range extends over the greater part of Africa, from Abyssinia to the Cape, and from East Africa to the Gold Coast. [3] The West African form of _Papilio merope_ has been quite recently distinguished from the southern form and regarded as a distinct species, the latter being now called _Papilio cenea_. The differences in the males are very slight--somewhat shorter wings, shorter wing-tail, and so on--differences which seem relatively unimportant in comparison with the differences between the males and the females. The male is a beautiful large butterfly, yellowish white, with a touch of black, and with little tails to the posterior wings (Pl. I, Fig. 1), like our own swallowtail. A very nearly related species occurs in Madagascar, and there the female is similarly coloured, though it may be distinguished by having a little more black on the wing. On the mainland of Africa, however, the females of _Papilio merope_ are so different in colour and form of wing that it would be difficult to believe them of the same species as the male had not both sexes more than once been reared from the eggs of one mother. The females (Pl. I, Fig. 6) in South Africa imitate a species of _Amauris_, _A. echeria_ (Pl. I, Fig. 7), of a dark ground-colour with white, or brownish-white, mirrors and spots, and they resemble it most deceptively. But what makes the case more interesting in its theoretical aspect is that _Danais echeria_ of Cape Colony is markedly different from _Danais echeria_ of Natal, and the female of _Papilio merope_ has followed those two local varieties, and has likewise a Cape and a Natal local form. Even this is not all, for in Cape Colony there are two other females of _Papilio merope_. One of them has a yellow ground-colour, and resembles _Danais chrysippus_, which is extremely abundant there (Pl. I, Fig. 3); the other is entirely different (Pl. I, Fig. 4), for it closely mimics another Danaid occurring in the same districts of Africa, and also immune, _Amauris niavius_ (Pl. I, Fig. 5), not only in the beautiful pure white and deep black of the wing surface, but also in the distribution of these colours to form a pattern.