Chap. XI. BUTTERFLIES AND MOTHS. 393 



cabbage-butterflies (Pieris), or the great swallow-tail 

 Papilio which haunts the open fens — for these butter- 

 flies are thus rendered visible to every living creature. 

 With these species both sexes are alike ; but in the 

 common brimstone butterfly (Gonepteryx rhamni), the 

 male is of an intense yellow, whilst the female is much 

 paler; and in the orange-tip (Anthoeharis cardamines) 

 the males alone have the bright orange tips to their 

 wings. In these cases the males and females are 

 equally conspicuous, and it is not credible that their 

 difference in colour stands in any relation to ordinary 

 protection. Nevertheless it is possible that the con- 

 spicuous colours of many species may be in an indirect 

 manner beneficial, as will hereafter be explained, by 

 leading their enemies at once to recognise them as 

 unpalatable. Even in this case it does not certainly 

 follow that their bright colours and beautiful patterns 

 were acquired for this special purpose. In some other 

 remarkable cases, beauty has been gained for the sake 

 of protection, through the imitation of other beautiful 

 species, which inhabit the same district and enjoy an 

 immunity from attack by being in some way offensive 

 to their enemies. 



The female of our orange-tip buttterny, above re- 

 ferred to, and of an American species (Anth. genutia) 

 probably shew us, as Mr. Walsh has remarked to me, 

 the primordial colours of the parent - species of the 

 genus ; for both sexes of four or five widely-distributed 

 species are coloured in nearly the same manner. We 

 may infer here, as in several previous cases, that it is 

 the males of Anth. cardamines and genutia which have 

 departed from the usual type of colouring of their genus. 

 In the Anth. sara from California, the orange-tips have 

 become partially developed in the female ; for her wings 

 are tipped with reddish-orange, but paler than in the 



