510 MR. TRIMEN ON MIMETIC ANALOGIES AMONG AFRICAN BUTTERFLIES. 



those of the southern examples of Hippocoon ; but the hind wings and the broad inner- 

 marginal space in the fore wings are coloured bt^ick-red instead of white ; and the butterfly 

 thus becomes a very fair imitation of Bauais Chrysippiis*. Tliis form of $ is even 

 rarer than Sippocoon, the number of specimens that I have seen in collections being 

 seven only, including two that I had the good fortune to capture in the Cape Colony, 

 one at Knysna, and the other at Plettenberg Bay t. Professor Westwood {loc. cit.) states 

 that Trophonins is a native of Guinea as well as Kaffraria. 



We have thus, as it appears to me, a most remarkable case of polymorphism in the 

 female of Fapilio Merope — three of the four forms being direct mimickers respectively 

 of three prevalent African species of Danals, while the fourth, differing from all the 

 others, yet closely related hj an intermediate variety to one of them, is probably modified, 

 or in course of modification, in mimicry of some other protected butterfly, possibly not 

 a Danais +. 



But another point remains for consideration. Papilio Merope (or its close ally) in 

 Madagascar, presents a female tailed and coloured like the male, and differing only in 

 the possession of a broad black bar on the costa of the fore wings, almost crossing the 

 discoidal cell.- That this is the rule in Madagascar cannot be doubted, as Mr. Plant's 

 collection contained a series of females presenting little or no variation. The examina- 

 tion of a number of examples from the island in question leads me to think that the form 

 there prevalent is constant in both sexes, and entitled to rank as a distinct species §. 

 But whether we accord or refuse specific rank to P. Meriones matters little to those 

 who hold that unmistakably close alliance between two or more forms is at once the 

 result and evidence of community of descent. Place the males from the island side by 

 side with those from the continent of Africa, and perhaps few would be disposed to 

 regard the former as specifically distinct from the latter ; and yet we find the female of 



Afrioaj Aiistralis,' published in 1861. Hopffer has recently (Stott. ent. Zeit. 1866, pp. 131-132) corrected the 

 mistake, pointing out that females of both forms are in the Berlin Museum. — Vide ' Zoological Eeeord ' (1866), p. 4.51. 



* A cuiious example, taken (in company with P. Merope) near St.-Lucia Bay in South-eastern Africa, \>y Col. 

 Tower, of the Coldstream Guards, is to some extent intermediate between the Trophonius and Hippocoon forms, the 

 broad whitish spaces being obscured throughout with a dull-oohreous tint. 



t It is worthy of notice that on each occasion of my meeting with Troplionius, I took, in the same spot, a specimen 

 of the Cenea form of 2 • 



X It may be objected that, in the strict sense of the term, this is not a true case of polymorphism, seeing that 

 intermediate varieties still occur which more or less connect the different forms. I am willing to admit that the 

 phenomenon is not yet absolutely complete; but the three forms that imitate the three species of Danals are already 

 so marked that the elimination of the few indi\iduals of intermediate or unstable character, that serve to link to 

 some extent two or more of those forms, will probably be the work of uo very extended period. 



§ In the insular form, the black border of the fore ivings forms much sharper projections inwardly on the nervules, 

 and the costal edging is brownish instead of black, in the S never extending below the subcostal nervure. The band 

 crossing the hind wings is always widely interrupted in two places, and the intermarginal black edging is wanting, 

 while the tails are all fuscous except the broad ochreous tip. On the underside, the ochreous colouiing is rather 

 paler and more rufous in tint ; and in the $ the hind ivim/s are clouded from the base, over the disioidal cell, and the 

 inner-marginal region with brownish. The spots of the head and thorax are yellowish, and in the S almost concealed 

 by a clothing of brownish hairs ; and the abdomen is without the ordinary dark spots (save some very faint traces in 

 the d ), being coloui'cd almost uniformly of the same pale yellow as the upper surface of the ^vings. 



