

THE PLACE OF MIMICRY 



case be adinittcd that the Ratesian interpretation is more 

 probable here than in other butterflies. But, for the 

 reasons L^iven in ihc discussion upon Protogoiiu^, it ap- 

 pears to me that the balance of probability is the other 

 way. The Elyvniiiuac beinj^, almost without exception, a 

 mimetic Sub-Eamil\-. we must certainly assume a mimetic 

 ancestor with (jualities determining^ mimc'tic descendants. 

 It has been alreacl)' shown that such a history is con- 

 sistent with the Miillerian interpretation, but with our 

 present knowledge difficult or perhaps impossible to 

 reconcile with the I)atesian Hypothesis (see p. 352). 



b. Dimorphic or Polymorphic Mimetic Ihitto'Jlics luifh 

 Forms Rcscf?idii)t<^ Different Models. — The phenomenon 

 described in the title of this Sub-Section is quite common 

 among mimetic species. Examples will be given in 

 a later part of this I^ssay (see pp. 372-5) showing 

 that the male and female of a mimetic species may 

 resemble different models ; that the male may resemble 

 one model, and two kinds of female two others ; that 

 a non-mimetic male ma}- be accomjjanied b) two, three, 

 or even four forms of female mimicking ditterent models. 

 The great example of this latter complex form of mimicry 

 is of course the Ethiopian J\ipilio dardanus (jticrope), 

 described on j^p. 373-5. 



At first sight such cases appear strongly to support 

 the Hatesian inter[)retation. His h)pothesis assumes 

 that the n-semblances are a fraud which, if detected, 

 would lead to the destruction of the mimic. It mav be 

 admitted that great increase in numbers would multipl}' 

 the chances of detection, and hence, upon the Batesian 

 Hy|>othesis, the advantage to a mimic of dividing its indi- 

 vi(hials among two. three, or four models instead of 

 concentrating all of them upon a single one. Accepting 

 this conclusion, I was much startled in 1902,' when 

 considering the African Acraeine butterfly, Acraea 

 escbria, to observe that tliis {protected and distasteful 

 species possessed two forms of mimetic female, both re- 

 sembling Danainae — one Limnas chrysipptis and the 

 other the black and white species oi Amaiiris. 

 ^ Trans. Ent. Soc, Loud., 1902. p. 469. 



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