xvi PREFACE 



and also two examples of the second, each mimicked by 

 a Pseudacraea with sexes alike ; and when, in 1910, 

 Dr. Jordan announced that these three Pseudacraeas could 

 not be separated structurally from each other, from the 

 Linnean West African eurytus, or from other mimics west, 

 east, and south, which had been described as distinct 

 species, I felt that the obvious conclusion that they were 

 in fact all of them forms of one and the same species 

 ought to be confirmed by breeding experiments before 

 it gained acceptance. And it was the occurrence, in the 

 same area, e.g. Uganda, and ex hypothesi interbreeding, 

 of forms with sexes different and with sexes alike, which 

 raised the greatest difficulty, and at the same time 

 would prove of the deepest interest if the conclusion 

 were confirmed. In order to test it I wrote to 

 every naturalist known to me who was in a position 

 to undertake the work, pointing out its exceptional 

 interest and importance. I even tried to persuade the 

 late Mr. A. D. Millar who had just been very successful 

 in breeding the Natal form of the Pseudacraea, to under- 

 take the journey to Uganda and apply his experience 

 there. 



The complete success finally attained by the author 

 on Bugalla may be gathered from the results fully set 

 forth in Chapter XI. Dr. Jordan's conclusions were 

 thoroughly confirmed, and the large group of conspecific 

 forms, now proved to interbreed in the same areas, and 

 interbreeding, it may be legitimately inferred, with those 

 of other areas when they meet on the boundaries, the 

 group of Pseudacraea eurytus, took its place beside that 

 of Papilio dardanus as one of the greatest examples of 

 mimicry in the world. 



This discovery was completed by another of equal 

 importance described in the same chapter, the evidence 

 that the mimetic patterns were only kept up to the mark 

 in islands where and when their models were relatively 



