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Show SEXUAL SELECTION. PART II .. CHAPTER XL INSECTS, continued.-ORDER LEPIDOPTERA. Courtship of butterflies- Battles- Ticking noise- Colours common to both sexes or more brilliant in the males- ExamplesNot due to the direct action of the conditions of l~fe- Colours· adapted for protection - Colours of n:ot~s.- D1splay- Perceptive powers of the Lepidoptera- Vanab1hty- Caus~s ~f the difference in colour between the males and females- MimJCkry,. female butterflies more brilliantly coloured than the malesBri< Yht colours of caterpillars- Summary and concluding rema~ ks on the secondary sexual characters of insects- Birds and: insects compared. IN this great Order the most interesting point for us is the difference in colour between the sexes of the same species, and between the distinct species of the same genus. Nearly the whole of the following chapter will "be devoted to this subject; but I will first make a few remarks on one or two other points. Several males may often be seen pursuing and crowding round the same female. Their courtship appears to be a prolonged affair,. fm I have frequently watched one or more males pirouetting round a female until I became tired, without seeing the end of the courtship. Although butterflies are such weak and fragile creatures, they are pugnacious, and an Emperor butterfly 1 has been captured with the tips of its wings broken from a conflict with another male. Mr. Collingwood in speaking of the frequent battles 1 Apatnra Iris : ~The Entomologist's W cekly Intelligencer,' 1859, p. 139. For the Bornean Butterflies see C. Collingwood, 'Rambles of a Naturalist,' 1868, p. 183. CHAP. XI. BUTTERFLIES .AND MOTHS. 387 ~etween the butter_flies of Borneo says, "They whirl "round ~ac~ other with t.he greatest rapidity, and appear to be InCited by the greatest ferocity." One case is lm~wn of a butterfly, namely the .Ageronia jeronia wluch ma~es a noise like that produced by a toothed wheel passmg under a spring catch, and which could be he~rd at the distance of several yards. At Rio de Janeiro this _sound was noticed by me, only when two were chasmg each other in an irregular course, so that it is probably made during the courtship of the sexes; but I neglected to attend to this point.2 Ever! one has admired the extreme beauty of many butterflies ~nd of some moths ; and we are led to ask, how h~s t~Is beauty been acquired ? Have their colours an~ diversified patterns simply resulted from the direct actwn of the physical conditions to which these insects l~ave been exposed, without any benefit being thus denved? Or have successive variations been accumulated and determined either as a protection or for some unknown. purpose, or that one sex might be rendered ~ttrachve to the other? And, again, what is the meanmg of the colours being widely different in the males and females of certain species, and alike in the two sexes of ot~er species ? Before attempting to answer thes~ questiOns a body of facts must be given. W1th ~ost of our English butterflies, both those which are beautiful, such as the admiral, peacock, and painted lady (Vanessre), and those which are plain-coloured such as the meadow-browns (Hipparchire) the Flex ' are _a l'l Th' . ' es I r~. IS IS al~o the case with the magnificent Hehcomdre and Danaidre of the tropics. But in certain 2 See my 'Journal of Researches' 18±5 p 33 Mr Doubl 1 h d et ect ed (' p roc. Ent. Soc.' l\Iarch 3' rd 18±, 5 · p 1· 23) · 1· ec ay as b . ' , · a pecu 1ar mem- Iatnodus .sahc at the ba~e of the front wings, which is probably connee e Wit the productiOn of the sound. 2 c 2 |