INSECTS 



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into the New World where the pattern form does not exist ? 

 For the basis of the theory of mimicry is that the enemies of 

 the insect are acquainted with every detail of the appearance 

 of the pattern form. 



The case of Papilio cenea is discussed by Prof. Poulton 

 i Q his book on the Colours of Animals (International Scientific 

 Series) as a particularly convincing illustration of the theory 

 of utility as the explanation of mimicry. The facts, according 

 to the researches of Mr. Eoland Trimen, are as follows : The 

 male of Papilio cenea in Africa has the usual characters of a 

 swallow-tail, possessing the special "tails" on the hinder 

 wings, and black, yellow, and brown markings. The, female of 

 Papilio cenea occurs in three different varieties, each of these 

 being stated to mimic a different species of Danaid belonging 

 to its district. One of these female varieties is distinguished 

 as P. cenea proper, and resembles Amauris echeria, both 

 occurring in South Africa. The resemblance is certainly 

 remarkable ; the female P. cenea does not possess the " tails," 

 it is much smaller than the male, and it has a great deal of 

 black or dark colour like Amauris echeria. A second form of 

 the female of P. cenea, called hippocoon, resembles Danais 

 niavius in South Africa, and both the mimic and the 

 mimicking forms are slightly different in Natal. Both are 

 black and white. A third form of the female of P. cenea 

 resembles Danais clirysippus in Cape Colony. 



It is further pointed out that in three regions, namely, 

 Madagascar, the island of Grand Comoro, and in Abyssinia, 

 three species of Papilio occur closely allied to P. cenea, but 

 having both sexes almost alike, and exhibiting no mimicry. 



Now, remarkable as these facts are, it is necessary to 

 observe that the male P. cenea is distinctly more conspicuous 

 than the Danaid species which the females resemble. If 

 then the male requires no protection from disguise, why 

 should the female require it ? The females evidently, so far 



