Evidence for the Theory 



Clytus arietis, the " wasp-beetle," as an example 

 of this. 



6. It is asserted that mimetic resemblances are 

 produced in the most diverse ways ; that the 

 modes whereby the similarity in appearance is 

 brought about are varied, but the result is 

 uniform. 



" A lepidopterous insect," writes Poulton 

 (p. 251), "requires above all to gain transparent 

 wings, and this, in the most striking cases that 

 have been studied, is produced by the loose 

 attachment of the scales, so that they easily and 

 rapidly fall off and leave the wing bare except 

 for a marginal line and along the veins (Hemaris, 

 Trockilium)." 



7. It is alleged that the imitator and imitated 

 are always found in the same locality. If they 

 did not do so no advantage would be derived 

 from the resemblance. It is further alleged that 

 where the mimicking species is edible it is in- 

 variably less abundant where it occurs than the 

 species it imitates. 



8. It is pointed out that it sometimes happens 

 that where in the mimic the sexes differ in 

 appearance, the male copies one species, the 

 female quite a different one. This is said to be 

 because the deception would be liable to be de- 

 tected if the mimicking species became common 

 relatively to that which is imitated. " We there- 

 fore find that two or more models are mimicked 



229 



