THE FLIGHT OF PSEUDACRAEA 243 



I have many times been deceived by these mimics 

 in the forests on the islands, until long association and 

 close familiarity enabled me to differentiate. But even 

 then, after a pause of a few weeks during which they 

 had not been seen, it was by no means easy to say 

 at a glance whether a specimen seen suddenly in the 

 forest was Planema or Pseudacraea. Certainly the mimics 

 are not so bold as Planema, and if really alarmed will 

 show it in their hasty flight, whereas the model is much 

 more stoical, and may be easily picked off a flower with 

 the fingers. 



The flight of Pseudacraea is often of the " floating " 

 nature, especially when several of these butterflies are 

 flying rather high up, in the sun, and round about a tree. 

 By this the mimic can be distinguished, but some species 

 of Pseudacraea, e.g. poggei, do not show the " floating " 

 flight to the same degree, and thus poggei bears an even 

 closer resemblance to its model, Danaida chrysippus, 

 whose flight is much more of the " flapping " type. 



Professor Poulton has written as follows about this 

 flight in a letter dated September 5, 1912 : "I am very 

 interested in the non-floating flight of the most distaste- 

 ful butterflies. But I have seen a kind of floating flight 

 in D. plexippus in America. Still this is not like our 

 Limenitis, and this latter I suspect is like Pseudacraea. 

 A floating flight for display, accompanied by alertness 

 and activity when alarmed, seems to be characteristic 

 of the second category of distasteful insects in Mullerian 

 combinations ; it is also true of the true Heliconinae in 

 South America, mimics of the Ithomiinae." Again, in 

 another letter, written March 6, 1912, Professor Poulton 

 said : "It is an extraordinarily interesting genus ; its 

 habits, I should think, are rather like those of our 

 Limenitis, and the degree of distastefulness I should 

 think about the same." 



The genus Pseudacraea, therefore, is to be regarded as 



