Xvt 



may be observed in the old world. As we have already noted, in the African 

 Danaid genus Amauris this follows the same course which characterizes the 

 African Papilio Dakdanus Brown. Still more striking is the arrangement of 

 the pigments producing the peculiar colour of Euploeas. But while this 

 character occurs in the whole of this specialized genus the same colouring 

 appears in a few species of various genera of Rhopalocera, living in the same 

 districts with them, in various degrees of resemblance, sometimes completely 

 as in Euploea's, at other times in a lesser degree, or even in one sex only, 

 as is the case with Dimorphias in South America, whereas in the others this 

 course of the evolution of colours has not, or at least not yet, been followed. 

 Hypoumnas Antilope Cram. (Anomala Wall.) in this respect has come to 

 resemble most a Euploea. The colour is completely that of a Euploea ; 

 in the (3 even a strong interference blue has been developed on the upper side 

 of the fore-wings, as in Euploea Midamus L., but of a lighter shade, sothat 

 the expert who, as happened to me, sees it on the wing in broad daylight, 

 although not in the glare of the sun, immediately distinguishes' both species in 

 spite of all ideas of mimicry. The interference colours are governed by the 

 form of the scales and the difference in this respect in two not allied 

 butterflies will presumably remain constant, however much the pigmental colours 

 may change. In addition white begins to make its appearance on the universal 

 brown in these Hypolimnas, as in Euploeas; at first in the form of white 

 dots and, in one island more and in another less, in white streaks along the 

 inner margin of the hind-wings, just, therefore, where in Euploea Climena 

 Cram. Sepulchralis Butl. the white is most developed, becoming diffused into a 

 broad border surrounding all the wings, just as in this and even other species 

 of Euploeas, in the K6 islands. In various species of Papilio, such as 

 P. Paradoxa Zinck, P. Canopus Westw., and others the colour evolution 

 has in general followed the same course as in Euploeas ; in some species, 

 such as P. Caunus Westw. and P. Agestor Gray, this has been carried so 

 far, as regards the white, that they acquire a strong so-called mimetic resem- 

 blance in colour to certain species of Euploea. In the Zygaenidae, a family 

 of Heterocera which appears to be specially susceptible to such influences, the 

 same Euploea colour occurs in a few species, most so in Isbaria Midamia 

 H-Sch. and Isbarta Militans Butl. Another species of Hypolimnas, H. Bolina 

 has, indeed, not shown itself as susceptible to this influence as H. Antiopa 

 Cram, but has not been able to escape it entirel)^ ; amongst the different forms 

 of the 9 of that species one occurs, Perimele Cram, in which the Euploea 

 colour appears likewise. In the c? of a species of Elymnias, E. Undularis 

 Drury the colour development of Euploea is also present, but in the 9 that 



