( Ixvii ) 



Exhibitions. 



Mimetic Relations of East and West African Butterflies. 

 — Mr. H. Eltringham exhibited examples of certain African 

 butterflies, and explained that when working out the mimetic 

 relations of Acraea alcio2)e, Auriv., he had been struck by the 

 fact that whilst in West Africa the female of that species was 

 well known, it having in fact been described from a female, 

 all East African examples were males. He had written to 

 Dr. Jordan to ask him if he had seen any East African females, 

 and the latter had replied that in East Africa alcio'pe appeared 

 to be I'epresented by the alicia of Grose-Smith and Kirby (errone- 

 ously described as a.Plane7na),ih.aX the alleged male (type) of this 

 latter species was in fact a female, and that in all probability 

 the East Afx^ican female alcio^je would be found to have white 

 hind-wings. Acting on this suggestion he had examined 

 various Acraeas from the neighboui^hood of Entebbe, and found 

 that Ac7'aea aurivillii, Staud., common in that region was 

 always female.* He had then visited Tring, where he found 

 that Dr. Jordan had already, some time previously, associated 

 aurivillii with alciope. It was found that the alleged male alicia 

 of Grose-Smith and Kirby was in fact an aberrant female, and 

 that the female which had been described as such was not dis- 

 tinguishable from aurivillii. A visit to the National Collection 

 showed that there aurivillii had been associated with alcio2)e 

 though less definitely, and that Mr. Heron had, with character- 

 istic insight, supplied a note to the effect that the supposed 

 male alicia was probably a form of female. The result of the 

 whole investigation was that in alciope we had an extremely 

 interesting and complicated case of mimicry. In West Africa 

 the female alciope was in an unstable condition, but, generally 

 speaking, mimicked a male Planema which was probably a 

 form of salvini. At Sierra Leone the pattern of the female 

 was fairly constant, but at Fernando Po intermediate varieties 

 were found, one example he had seen having the fore-wings of 

 the Western type and the hind-wings almost as in aurivillii. 



* lu the hurry of his departure for Africa, Mr. Neave erroneously 

 described the examples of aurivillii in the Wiggins collection (Novit. Zool. , 

 Vol. II, 1904) as males. They are certainly females, as are all the speci- 

 mens, some fifty or more, examined by me. — H. E. 



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