160 MIMICRY IN N. AMERICAN BUTTERFLIES 



evidence. The following comparisons clearly indi- 

 cate that Danaida is an Old World genus which has 

 invaded America at no very remote period : (1) 

 the far larger number of the Old World forms 

 and the greater degree of specialization by which 

 some of them are distinguished ; (2) the place of 

 Danaida as one out of a number of nearly related 

 genera making up the Danaini, a large and 

 dominant Old World group, per contra its isolated 

 position in the New World ; (3) The highly 

 developed and complex mimetic relationships of 

 the Old World Danaidas. 



This last statement requires some expansion 

 and exemplification. Allusion has already been 

 made to the resemblances which have grown up 

 between different species of Danaida in the same 

 island, resemblances in which the forms of 

 chrysippus appear to act as models. Even more 

 striking is the mimetic approach of certain Old 

 World Danaidas to species of the other dominant 

 Oriental section of the Danainae the Euploeini. 

 Thus in the Solomons, Danaida (Salatum) insolata 

 is a beautiful mimic of the dark white-margined 

 Euploea brenchleyi, while in the same islands, 

 Danaida (Salatura) decipiens mimics the dark, 

 white-spotted Euploea asyllus. 1 Finally, and most 

 convincing as evidence of long residence, are the 

 numbers of mimics which in the Old World have 

 taken on the superficial appearance of species of 



1 See J. C. Moulton in Trans. Ent. Soc. Lond., 1908, 603, 604 : 

 PL XXXIV, figs. 5, 10. 



