VALIDITY OF SOME FORMS OF MIMICRY. 703 



in Trans. Ent. See. Lend, for 1908 will show, are extremely alike, 

 yet under certain circumstances I can recognize them when on 

 the wing without great difficult}'. When herded together in 

 shady jungle, as is their frequent custom, it is impossible to differ- 

 entiate them ; but when flying singly over an open space, the 

 former appears a blacker and broader insect with a rather more 

 flapping flight, by which I can usually distinguish it from E. core. 



The resemblance between Danais clirysippus and Hypolimnas 

 misippus $ is well known, and I haA^e often found them mixed 

 together in local collections, but on the wing under ordinary 

 circumstances differential diagnosis is by no means impracticable : 

 the female of the latter is almost invaiiably seen flying close to 

 the ground selecting favourable situations for oviposition, and 

 her method of flight, difficult to describe, differs from that of 

 D. chrysippus, which oviposits on a shrub some four or five feet 

 in height ; when not tlius engaged the two are undoubtedly 

 difficult to distinguish at about ten yards distance, and it is 

 curious how often the male of H. inxsippus mistakes D. chrysippus 

 for a female of its own species. Prioneris sita can at once be 

 distinguished from Delias e^icharis by its rapid darting flight. 



A case of resemblance, though not always stated to be one of 

 mimicry, is that of Argynnis hyperb'ms female and Danais plex- 

 ippus or D. chrysippus. This was remarked on by Butler so long- 

 ago as 1884 and has been repeatedly noticed since, particularly 

 by Longstaff and Bainbrigge Fletcher. The resemblance is, 

 however, entirely accidental, as their habitat in S. India and 

 Ceylon clearly shows. Broadly speaking, if observed above 4000 

 feet, it will assuredlj^ be A. hyperbins, if on the littoral and up to 

 about 4000 feet, almost certainly D. plexipjnts ; it is onl)'- on the 

 confines of each other's territory that they in any way come in 

 contact and where an error can be made. Cethosia nietneri, 

 Danais ceylonica, and Papilio clytia (dissimilis) fly in the same 

 localities, that is, in jungle where the light is very flickering. It 

 is not only very difficult to distinguish them apait, but they are 

 quite difficult to see, as their black and white marking tends to 

 make them invisible. They also frequent the outskirts of jungle 

 and even more open countiy, and here they ai'e quite easy to 

 distinguish, particularly P. clytia [dissimilis), which is a larger 

 and much yellower buttei'fly. 



Mr. T. Bell considers Cethosia to be an unpalatable genus owing 

 to the nauseous juices and leathery bodies of the species. Eitripus 

 consimilis very closely resembles a Danaid in both sexes, and 

 would be considered an undoubted case of either ]3atesian or 

 Miillerian mimicry : it is not a Ceylon butterfly, and I first 

 made its acquaintance in the Nilgiris ; by its lofty sailing flight, 

 particularly in the female, I recognized it at a glance from a 

 Danaid, which rarely or never ascends more than about ten feet 

 from the ground. 



It is more in their peculiar manner of flight rather than in 

 any difterence of colouring that model and mimic can as a rule 



