BEDROCK 



In attempting to explain this example of Mimicry we may clear 

 the ground by dismissing the hypothesis of Bates (1) and that of 

 External Forces (3). 



Acrcea alciope belongs to another genus of the same distasteful 

 sub-family as its Model. Mr. Lamborn has found by experiment that 

 it is distasteful to the same insect-eating animals. Its non-mimetic 

 male (Fig. 4) is furthermore mimicked by the female of Mimacrcea 

 fulvaria, one of the Lyccenidce — the family to which our British 

 " Blues," " Coppers," and " Hairstreaks " belong. The probable 

 male of M . fulvaria has been recognised by Mr. H. Eltringham in a 

 large West African Lycaenid which mimics the Pla nema-models of 

 the female alciope. If this identification be confirmed, we have a 

 good example of the tangled relationship so often found in Miillerian 

 combinations. The female of alciope, and the male of fulvaria both 

 mimic the same Planemce, while the female of fulvaria mimics the 

 non-mimetic male of alciope. 



The Batesian hypothesis does not explain the resemblance of 

 the distasteful female Acrcea to a distasteful male Planema. 



The fact that the physico-chemical forces of the locality have not 

 brought about the mimetic resemblance of alciope is sufficiently 

 shown by the fact that the non-mimetic male and the mimetic 

 female are both developed from gregarious larvae, living together 

 under precisely similar conditions. The specimens represented in 

 Figs. 3 and 4 are two out of a large company developed from the 

 same batch of eggs found by Mr. Lamborn on a single leaf, and evi- 

 dently laid by a single female. The larvae hatched on November 21st, 

 1910, were fed on the same food-plant, and together with the 

 pupae were kept under uniform conditions. This was the twelfth 

 in a series of companies of which each was raised in the same way 

 by Mr. Lamborn from a batch of eggs, or from minute recently 

 hatched larvae found upon a single leaf. The males, which have 

 not yet been counted, were all non-mimetic and similar to those 

 found wild in the locality ; the 249 females were all mimetic and, 

 with a single exception (see p. 63), also similar to the wild forms of 

 the Lagos district. 



In attempting to account for the origin of these mimetic females 

 we can only look, among existing hypotheses, to the growth of a 

 Miillerian resemblance by the operation of Natural Selection (2), or 



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