MIMICRY IN INSECTS. 63 



then advanced as in the highest degree probable has since been 

 incontestably demonstrated by the observations of Mr. Mansel 

 Weale, who, in 1873, reared all the four forms from eggs laid on 

 the white iron- wood {Vepris lanceolata) by a specimen of P. cenea. 

 Mr. Weale's researches and their result have recently been 

 confirmed by Colonel Bowker's notes on the sexes in Natal. 



We have thus the remarkable case of a butterfly, in which the 

 male is of a certain conspicuous and unusual coloration, which 

 varies but little, while the female is of three quite different 

 forms, each of which is entirely unlike the male, but imitates one 

 of the three prevalent species of Danainse inhabiting South 

 Africa ! It should be added that numerous intermediate variations 

 of the females exist, which exhibit a series of links between the 

 three prominent forms, and serve to indicate how plastic for 

 further development in any advantageous direction the polymorphic 

 female P. cenea remains. 



Other circumstances which add to the great interest of the 

 case are (1) that the very closely-allied true Papilio merope of 

 Western Africa also has a polymorphic female, several forms of 

 which have been described as distinct species, and are found 

 imitative of Danainse inhabiting the same region ; and (2) that in 

 Madagascar the likewise closely-related Papilio meriones has but 

 one form of female, and that form slightly different from the 

 male ! What is even more surprising is the fact, communicated 

 to me by Mr. Ch. Oberthiir in 1882, that the representative of 

 Papilio merope at Lake Tsana, in Abyssinia, also has the sexes 

 almost exactly alike. The inference is obvious that the females 

 in Madagascar and Abyssinia for some reason do not stand in 

 need of the protective disguises so elaborately worked out for 

 them in Southern and Western Africa. Probably some active 

 persecutors of this large pale type of Papilio are absent in those 

 countries, or may there have found some easier or more attractive 

 insect prey. In S. Africa the handsome flycatcher, Tehitrea cristata, 

 has been seen by Mr. Weale to capture the male P. cenea, and he 

 had reason to suspect a bird of an allied family and quite similar 

 habits, Dicrurus musicus, to be another of this butterfly's enemies. 

 Insectivorous birds of both these genera are found in Abyssinia — 

 the very same species of Dici'urus is, I believe, a native of that 

 country — and also in Madagascar; but it is possible that 

 circumstances may have led to their leaving Papilio merope and 

 P. meriones unmolested. 



