440 



SCIENCE. 



[N. S. Vol. VII. No. 170. 



Oriental region (as Col. Swinhoe has 

 pointed out in the paper above mentioned, 

 and has more folly of late described to 

 me) the same state of things is prevalent, 

 extensive Miillerian inedible associations 

 among (e. g. ) the species of the three main 

 groups into which the old genus Ertplcea 

 has been divided, being 'attended and sur- 

 rounded ' by numerous true mimics belong- 

 ing to edible groups. The far poorer Ethi- 

 opian region has, to my knowledge, yielded 

 as yet only a few series including both in- 

 edible and edible imitators ; but in the 

 group of which the Danaine Amauris egialea 

 is the center there appears the exactly 

 similar Danais {ilelinda) morgeni; and in 

 the same way the much-mimicked Amauris 

 echeria, var., has in East Africa a protected 

 companion in the female Aci-cea johnstoni, 

 while there is some reason for thinking 

 that the widely-distributed Aercea encedon is 

 modified in resemblance to the dominant 

 Danais chrysippus. Perhaps the most re- 

 markable of these associations is that 

 which surrounds the abundant and ex- 

 tremely conspicuous slow-flying diurnal 

 Lithosiid moth, Aletis helcita. The appar- 

 ently protected analogues of this insect are 

 the closely similar Lithosiid Plumgarista 

 heleitoides and Agaristid Eiiseinia falken- 

 steinii, while the Batesian mimickers are 

 found in the Nj^mphaline butterflies, Eu- 

 phcedra ruspina and E. eleits, and the aber- 

 rant Lycffinid, Liptena sanguinea. Another 

 point of interest in this last-named series is 

 its great similarity in coloring and marking 

 to that which is headed by Danais chry- 

 sippus, the differences being merely that in 

 the Aletis set the red ground- color is 

 brighter and the white spots in the black 

 margins are larger ; so that from the aspect 

 of warning of distastefulness to enemies the 

 two sets may be regarded as practically but 

 one. 



Among the Batesian mimicries in the 

 Ethiopian region, I wish to revert more 



fully to the very striking and instructive 

 case, already briefly referred to, presented 

 by the females of the Merope group of the 

 genus Papilio, because it has largely gained 

 in interest by the increase of our knowledge 

 in recent years. In 1867, when I wrote 

 the paper above mentioned,* only three 

 forms of the Merope group were known, 

 vid. : the AVest African P. merope, the South 

 African P. cenea (then regarded as not more 

 than a variety of P. vierojye), and the Mada- 

 gascar P. meriones. Of these the last-named 

 alone had the sexes nearly alike, vid. : of a 

 very pale yellow, margined with black in 

 the forewings, and with the hind wings 

 more or less black-marked and bearing con- 

 spicuous tails ; each of the two continental 

 species presenting not only the utmost dis- 

 parity between the sexes, but also the 

 singular phenomenon of a polymorphic fe- 

 male, invariably without tails, accurately 

 mimicking two or three widely-differing 

 species of Danainse, and at the same time 

 offering numerous linking variations. I 

 was justified in considering that the Mada- 

 gascar form should be regarded as retaining 

 the ancestral condition of this group of 

 Papilio, while the females of the continental 

 forms had been profoundly modified in the 

 mimetic directions specified ; and I pointed 

 to the costal black bar in the fore wings of 

 the female P. meriones as possibly indica- 

 ting the feature on which natural selection 

 had been able to work, to the ultimate pro- 

 duction of close imitation first of the 

 lighter and at length of the darker Dana- 

 inse concerned. 



It was startling to learn, in 1883, that a 

 newly-discovered continental form of the 

 group, P. antinorii, inhabiting Abyssinia, 

 like the Madagascar P. meriones, had the 

 sexes quite alike, except for the costal black 

 bar in the female ; while in 1889 there 

 was described from the Comoro Islands a 

 fifth and very distinct species, P. Immhloti, 



* Trans. Linn. Soc, XXVI. 



