MIMETIC ASSOCIATIONS 



83 



MIMICRY IN THE PI ERIN AE 



It might be supposed that, in view of the conspicuous appearance of the Pierinae, 

 mimicry produced by close resemblances in detailed markings would be to some extent 

 overshadowed by the predominating feature of white wings. Nevertheless there is consider- 

 able evidence that the detailed characteristics of what in Africa appears to be the dominant 

 genus, viz. Mylothris, are faithfully copied by species of several other genera, notably by 

 forms of Phrissura, which constitute mimetic pairs with many species of the former genus. 

 The forms of Mylothris are themselves extremely difficult to differentiate into species, and 

 pending further investigation I have followed the specific names given by Professor Aurivillius 

 in his ' Rhopalocera Aethiopica', wherein are enumerated some twenty-eight species. The 

 exceedingly accurate mimicry which obtains between species of different genera of African 

 Pieridae has been productive of considerable confusion of nomenclature. To deal adequately 

 with the subject of Pierine mimicry would involve a careful revision of the species and genera, 

 and an exhaustive study of many varieties, all of which would be inappropriate to the scope 

 of the present work. In spite of a sense of incompleteness I must content myself, therefore, 

 with calling attention to the Pierine forms certainly belonging to different genera which 

 exhibit apparently mimetic patterns. Any lack of unanimity at present existing as to the use 

 of certain specific names does not materially affect the aim of the work. 



MYLOTHRIS AGATHINA. 



Cramer, Pap. Exot., iii, p. 76, pi. 237, ff. D, E (1779). 

 Trimen, S. Af. Butt., iii, p. 30 (1889). 

 — Metamorph. S. Af. Butt., iii, p. 31, pi. 2, f. 3 (1889). 

 Aurivillius, Rhop. Aeth., p. 394 (1898). 



Plate IX, Fig. i, o^. Fig. 9, 5. 



The female M . agathina varies from the appearance shown on Plate IX to a rich orange 

 colour, the vermihon flush at the base of the fore-wing being more or less accentuated. The 

 species has a wide range, apparently occurring over the whole of Tropical Africa. The larva 

 and pupa are thus described by Trimen : — 



' Larva. Transversely barred with alternate dull red and blackish bands speckled 

 with yellow- ; and clothed generally with fine grey hair of some length ; a yellowish- white 

 lower lateral stripe on each side, from second to last segment immediately above the legs. 

 Head black, varied with yellow down the middle. Length, | inch. 



' Pupa. White, more or less tinged with cream-colour in parts, and curiously marked 

 with black. Head with a long frontal horn, curved upward, cream-coloured. Thorax cream- 

 coloured dorsally, but with a broad black marking along the middle ; a small anterior acute 

 black tubercle on each side, and on median ridge a series of three white, black-edged, broad, 

 blunt, tubercular processes, slanting forward. Wing-covers black with a greenish tinge. 

 Abdomen dorsally white and black, the latter forming a large lozenge-shaped marking 

 (widest on seventh segment) acuminate anteriorly on fifth and posteriorly on ninth segment ; 

 on each side a row of small black spots ; below these a broad black stripe ; along median 

 ridge a series of seven small white black-edged tubercles, of which the second, third, and 

 fourth are blunter and larger than the rest ; both the sixth and seventh segments bearing 

 on each side a large, broad, acute, slightly forward curved, tooth-like white projection ; 

 anal extremity very pointed. Length f inch. Attached by anal extremity and thoracic 

 silken girth to web of silk spread on a leaf.' 



