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MIMICRY IN THE TWO SEXES OF THE EAST AFRICAN 

 LYC.ENID, AL.ENA PICATA E. M. SHARPE. 



By K. St. Aubyn Rogers, Mombasa. 



Many cases of mimicry amongst African Lyccenidce are well 

 known, most of which are found amongst the Liptenince. The 

 reason for this is that this large group, or at any rate many 

 genera of it, have quite different habits from the more typical 

 Lycaenids. They are almost entirely confined to forests, and 

 do not frequent flowers. They may usually be seen floating 

 about in sunny openings, or settling on the branches of trees 

 with the wings hanging down. 



The species which is the subject of this note is remarkable 

 for its marked sexual dimorphism, which is very unusual in 

 the subfamily. The female was first described, and was named 

 by Miss Sharpe Alœna picata. This is a small black-and-white 

 insect, and although the distribution of the markings is rather 

 different from those of any Ncptis which inhabits the same 

 district, still the floating character of its flight gives it a very 

 marked resemblance to this genus on the wing, and it is not 

 easy, at first, to distinguish it from some of the smaller specimens 

 with which it flies. 



The male, on the other hand, which has more recently been 

 called Alœna vollei, has all the light markings bright fulvous, 

 and their distribution diflers somewhat from those of the female. 

 It bears a general resemblance to a small Acrcea. 



This sexual dimorphism is excessively rare in the whole 

 subfamily of Liptenince, and it is of great interest that it appears 

 to be connected with mimicry of butterflies belonging to diflerent 

 subfamilies. 



There can be little doubt that the two forms are male and 

 female of the same species. On the underside the resemblance 

 is very close. They come from the same locality, whereas no 

 other species of the genus is known from the district, and the 

 white-marked specimens are always female and the fulvous- 

 marked specimens always male. 



