Archive image from page 351 of The descent of man, and. The descent of man, and selection in relation to sex descentofmansel01darw Year: 1871 334 SEXUAL SELECTIQX. [Part II. 'nnd obviously for the same end.' In male dragon-flics, 'the appendages at the tip of the tail are modified in an almost infinite variety of curious patterns to enable them to embrace the neck of the female.' Lastly, in the males of many in- sects, the legs are furnished with peculiar spines, knobs, or spurs; or the whole leg is bowed or thickened, but this is by no means invariably a sexual character; or one pair, or
Archive image from page 351 of The descent of man, and. The descent of man, and selection in relation to sex descentofmansel01darw Year: 1871 334 SEXUAL SELECTIQX. [Part II. 'nnd obviously for the same end.' In male dragon-flics, 'the appendages at the tip of the tail are modified in an almost infinite variety of curious patterns to enable them to embrace the neck of the female.' Lastly, in the males of many in- sects, the legs are furnished with peculiar spines, knobs, or spurs; or the whole leg is bowed or thickened, but this is by no means invariably a sexual character; or one pair, or all three pairs are elongated, sometimes to an extravagant length.' In all the orders, the sexes of many species present difierences, of which the meaning is not understood. One curious case is that of a beetle (fig. 9), the male of which has the left mandible much enlarged; so that the mouth is greatly distorted. In another Carabidous beetle, the Eurygna- thus,' we have tlie unique case, as far as known to Mr. Wollaston, of the head of the female being much broader and larger, though in a variable degree, than that of the male. Any number of such cases could be given. They abound in the Lepidoptera: one of the most extraordinary is that cer- tain male butterflies have their fore-legs Fi 9 â Taphro- 'rc or Icss atrophied, with the tibioD and deres (listortus tarsi reduced to mere rudimentary knobs. (much enlarged). â¢' Uppur ligiirc. hc wincTS, also, in the two sexes often differ male; lower flg- b â > i ure, female. jji ncuratiou,'' and sometimes considerably about Pcnthe, and others in inverted commas, are taken from Mr. Walsh, ' Practical Entomologist,' Philadelphia, vol. ii. p. 88. Kirby and Spence, ' Introduct.' etc., vol. iii. pp. 332-336. ' 'Insecta Maderensia,' 1854, p. 20. ' E. Doubleday, 'Annals and Mag. of Nat. Ilist.' vol. i. 1848, p. 379.
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