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M. E. B. PouLTON (Oxford) prend ensuite la parole pour exposer : 
Mr. C. A. Wiggins’ researches on mimicry in the Forest 
Butterflies of Uganda (1909). 
(Résumé.') 
The memoir printed m the second part of this volume contains 
an account of Mr. Wiggins’ admirable observations on a certain 
dominant of Planema- models (. Acrœinœ ) and their numerous 
mimics, between May 23rd, and August 31st, 1909. These models 
provide three very different and clearly defined patterns. The 
captures were made in a patch of virgin forest, near Entebbe, on 
the north-west shore of the Victoria Nyanza, and the results of at 
least thirty days work are tabulated for each of the three patterns 
with their mimics. We thus obtain the most conclusive evidence 
that model and mimics fly together, for they were taken in the 
same area and on the same days. 
The three combinations are as follows : 
I. The male of Planema macar isla and both sexes of PL poggei 
with their mimics : the female of Acrœa alciope , the male of 
Pseudacrcea hobleyi, both sexes of Ps./men orni, and the female form 
planemoides of Papilio dardanus dardanus. Incipient mimicry is 
also found in some individuals of Pseudacrcea albostriata, throwing 
light upon the origin of mimetic resemblance. Occasional females 
of A. alciope resemble a western type, mimetic of the common 
appearance of western male Planemas. They make us to under¬ 
stand how a mimetic form may assume a new pattern in an area in 
which it meets a new and dominant model, and how the older 
pattern may be gradually eliminated in that area. Of the two 
mimetic Pseudacrceas, Ps. hobleyi ç? more dosel}' - resembles 
PI. macarista rf, while Ps. ì'menomi resembles PI. poggei. A single 
female of Ps. hobleyi possessing the mimetic pattern of the male 
was captured May 18th, 1909. The relative abundance of models 
and mimics in this and the two following combinations has an 
important bearing on theories of mimicry. 
Two interesting mimics belonging to this association were not 
captured by Mr. Wiggins in the period under consideration : a 
local form of Elymnias phegea, and the female of Precis rauana. 
