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AFRICAN MIMETIC BUTTERFLIES 



the value of the somewhat Acraeine appearance of Byhlia ilithya by offering them with the 

 underside exposed. They were eaten wdth evident appreciation. Acraea rahira was then 

 offered in the same manner, but the animal recognized it and threw it down without even 

 smelling it. Two more ilithya were then eaten, and an^. axina and B. ilithya, being offered 

 together, the animal ate the latter and neglected the former. The baboon was clearly able 

 to distinguish between these two butterflies by their pattern. Some doubt about ilithya was, 

 however, shown on a later occasion, when the baboon pulled one to pieces and threw it down, 

 then, changing its mind, picked up the thorax and ate it, immediately afterwards eating three 

 more specimens in quick succession. On another occasion Precis archesia, two male H. misip- 

 pus, two B. ilithya, three A . phalantha, and one P. sesamus (wet form) were eaten, whilst M. aga- 

 thina, A. natalica, and P. sesamus (dry form), were refused. M. agathina was subsequently 

 eaten with reluctance, and a second example was refused after tasting. Neptis agatha was 

 treated in the same way, but two B. severina were eaten with relish. P. sesamus and H. misip- 

 piis f. inaria were readily eaten. Two large Hesperidae were eaten ' with avidity ' and the 

 baboon watched with great eagerness the opening of another box, being obviously dis- 

 appointed on receiving B. mesentina, which, however, was eaten. Herpaenia eriphia, after 

 being carefully tasted, was rejected. As showing the comparative distastefulness of M. aga- 

 thina, Mr. Marshall describes how the baboon seized that insect and B. mesentina, and began 

 eating them both at once. It then put them out and picked up the Mylothris, tasted it and 

 threw it away, afterwards eating the Belenois. The other baboon picked up the Mylothris, 

 but after tasting it also at once threw it away. 



These results are amongst the most interesting and conclusive yet recorded, and it is 

 greatly to be desired that further experiments will one day be made. In view of what has 

 been described we can no longer entertain the slightest doubt that many butterflies are in 

 fact nauseous to insect-eating animals, whilst others are obviously much relished. That 

 tastes differ somewhat is also shown by the difference in the behaviour of insects, reptiles, 

 birds, and mammals, and this is what we should naturally expect, since it is manifest that 

 even generally unpalatable species cannot be protected from all their foes, otherwise they 

 would multiply indefinitely. Since some species are undoubtedly protected by their dis- 

 tastefulness, the theory of mimicry must stand on a sound basis, as, given this one fact, 

 it follows that outward resemblance to such protected kinds must of necessity be an advan- 

 tage to an edible species, and this conclusion is not in the least affected by any arguments 

 as to the manner in which such resemblance may have been brought about. Endeavours have 

 been made to show that insects which are distasteful to their enemies are not possessed 

 of any nauseous qualities whatever, since certain naturalists have, albeit with most praise- 

 worthy devotion to science, overcome their natural disinclinations, and actually tasted 

 butterflies and moths. Professor Fehx Plateau ^ tasted the larva, pupa, and imago of the 

 Magpie moth, so persistently refused by birds. He describes the larva as devoid of any 

 unpleasant flavour, in fact rather agreeable than otherwise, and somewhat recalling that 

 of sweet almonds or cocoanut. The pupa and imago produced a similar impression, though 

 to a feebler extent. Professor W. M. Wheeler, of Texas University, also tasted some con- 

 spicuous day-flying moths [Pseudohazis) with precisely similar results.^ Mr. Marshall himself 

 made some tasting experiments on African butterflies.^ He describes A. encedon as exuding 

 a slightly bitter juice from the thorax. A. anacreon and natalica a similar juice, but ' dis- 

 tinctly more bitter ', whilst A. anemosa emits both the bitter juice and a very strong smell. 



1 See Mem. dc la Soc. Zool. de France, 1894, p. 375 (quoted by Poullon, Trans. Ent. Soc, 1902, p. 405). 



2 ' Century Magazine,' 1901, p. 378 (also quoted by Puulton). ^ Trans. Ent. Soc, 1902, p. 413. 



