36 SOUTH-AFEICAN BUTTEEFLIES. 



four butterflies (of three different groups) and a Moth all copy the 

 Danaine Ithomia Flora. The imitations of species of ItJiomia, Mecha- 

 nitis, and IfetJiona, Danaine genera, by species of Lejjtalis, a genus of 

 Fierince, are so surprisingly exact, that no one can wonder at their 

 deceiving on the wing the most experienced collector. 



Mr. Wallace, in 1864, called attention to the occurrence of a 

 similar series of mimicries in India and the Malayan Archipelago, and 

 expressed his full concurrence in Mr. Bates's view of the causes at 

 work in the production of them. The list given in his paper 

 (Trans. Linn. Soc, xxv. p. 20) includes fifteen cases where species of 

 Papilio mimic Danainw, Nymphalince (one case), and other forms of 

 their own genus.-^ The first of these may be noted as peculiarly 

 interesting, seeing that the male and female of the mimicker, Papilio 

 paradoxa, differ considerably, and that each imitates the corresponding 

 sex of Euplcea Midamus. In seven of the fifteen cases given, only the 

 female is mimetic ; and Mr. Wallace suggested that the reason for this 

 is probably that the slower flight of that sex when laden with eggs, 

 and her exposure to attack while ovipositing, render a protective dis- 

 guise specially necessary.^ 



It was most interesting to me to be able to supplement the cases 

 brought forward by these distinguished explorers of South America and 

 the Malayan Archipelago by a corresponding series of mimetic analogies 

 among African butterflies. The cases in life known to me personally 

 in South Africa were only four, but it so happens that one of them was 

 the most remarkable ever recorded, viz., that of Papilio Cenca. I 

 found, however, seven other very marked mimicries among the butter- 

 flies of Tropical Africa, and several additional instances (two of them 

 in South Africa) have since then (1868) been discovered and placed 

 on record. I was able to show^ (1°) that the Banaince and Acrceince 

 of Africa, like their allies elsewhere, were provided with offensive 

 odours and secretions ; (2°) that the butterflies mimicking them invari- 

 ably occurred in the same districts, and in six cases (South African) in 



which, on the ground " that a certain number of individuals of distasteful species have to be 

 sacrificed to the inexperience " of young insectivorous animals, he shows that " there would 

 be a great gain in one distasteful species resembling another which exceeded it in numbers." 



Mr. Bates (loc. cit., p. 503) marks six of the imitating Danaincc as undoubtedly very 

 much fewer in individuals than the species which they imitate ; so that the fact of their 

 being for some reason in need of protection seems established. 



■* Mr. Wallace observes (p. 21) that these imitated Papilios of the East belong to the 

 group of Papilio Polydorus and P. Coon, and that, like the ^^neas group of Papilio in South 

 America, they are forest insects and have a low, weak flight. What their protection con- 

 sists in has not been ascertained, but most probably it lies in their being unpalatable as food. 



2 A most striking case of this kind is that recorded by Mr. Wallace (Trans. Ent. Soc. 

 Lond., 1S69, p. 287). Diadema anomala, a Nymphaline of the Malay Archipelago, has the 

 male plainly tinted with bronzy or olive brown, only a blue gloss appearing on the margins of 

 the fore-wings ; while the female is rich purple-brown, with two-thirds of the fore-wings 

 richly glossed with satiny blue, so as to closely imitate Euplxza Midamus, a protected 

 Danaine, " one of the very commonest butterflies of the East." 



3 Trans. Linn. Soc. Lond., xxvi. p. 497, &c. 



