A MIMETIC SPECIES MIMICKED 217 



and an additional smaller patch at the apex of the fore-wing. 

 The under side, although different from the upper, is 

 also conspicuous, and evidently belongs to a very different 

 category from, e.g., the leaf-like under sides of Kallima. 



If the remarkable cryptic coloration and attitude of this 

 latter is held to be indirect evidence that the species is 

 palatable to insect-eating animals, it follows that such an 

 under side as that of the male H. misippus constitutes 

 indirect evidence of unpalatability, in other words that it 

 is a warning (aposematic) appearance. 



If the argument set forth above be sound, it is obvious 

 that the mimetic females of Hypolimnas have, in their 

 past history, merely exchanged a conspicuous warning 

 pattern characteristic of the genus for conspicuous patterns 

 borne by distasteful forms inhabiting the same country. 

 In other words, the evolution has been of the kind we 

 should expect upon the Mullerian theory. 1 



And now in recent years astonishing evidence in 

 support of the same conclusion has been forthcoming. 

 The non-mimetic male of Hypolimnas misippus is itself 

 beautifully mimicked on both upper and under sides by 

 two Nymphaline butterflies in Western China — Limenitis 

 albomaculata and Athyma punctata. 



The model is abundant in the tropics far away to the 

 south, but becomes much rarer in Northern India, and has 

 never been known in Western China, where its mimics 

 are found. We are driven to suggest two alternative 

 hypotheses: (1) The model, with its immense powers of 

 flight, has visited Western China sufficiently often and 

 for long enough periods to render the mimetic resemblance 

 advantageous. Against this it may be urged that 

 H. misippus is a tropical butterfly, and it is most improb- 

 able that it would reach, or at any rate establish itself, 

 in such a latitude and elevation as, e.g., Ta-tsien-lu ; 

 (2) A more probable hypothesis is afforded by the lines 

 of migratory birds, applying in the temperate zone, where 

 they nest, the experience learnt in the tropics. If a bird's 

 experience of H. misippus be an unpleasant one, it follows 



1 See Proc. Amer. Ass. Adv. Set., 1897, vol. xlvi, p. 242 ; also Trans. 

 Ent. Soc. } Lond., 1902, pp. 500-2. 



