. The descent of man and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings. 331 SEXUAL SELECTION. [Paut " and obviously for the same ; Li male dra-on-flies Hhc appendages at the tip of the tail are modiM in an' almost infinite variety of curious patterns to enable them to embrace the neck of the ; Lastly, in the males of many in- sects, the legs are furnished with i)eculiar spines, knobs, or 8j)urs; or the whole leg is bowed or thickened, but this is by no means invariably a sexual character; or one pair, or all three i)air8 are e
. The descent of man and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings. 331 SEXUAL SELECTION. [Paut " and obviously for the same ; Li male dra-on-flies Hhc appendages at the tip of the tail are modiM in an' almost infinite variety of curious patterns to enable them to embrace the neck of the ; Lastly, in the males of many in- sects, the legs are furnished with i)eculiar spines, knobs, or 8j)urs; or the whole leg is bowed or thickened, but this is by no means invariably a sexual character; or one pair, or all three i)air8 are elongated, sometinn s' to an extravagant length.' In all the orders, the sexeg of many species j)resent difl'erences, 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," wc have the 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, l^hey abound in the Lepidoptera: one of the most extraordinary- is that ccr- •'' ' tain male butterflies have their fore-legs Fio. '"^re or less atrophied, with the tibia and (lunvh ciilari,'c(l(. tarsi reduced to mere rudimentary knobs. innirriuwcrXr: "^^^^ wings, also, in the two sexes often differ urc, female. ncuration,'" and sometimes considerably about Penthc, and others in inverted comroa*, arc taken from Mr. Walsh, ' Pnictical Entomologist,' Philadelphia, vol. ii. p. 88. " Kirby and Sponce, ' Introduct.' etc., vol. iii. pp. 332-336. • 'In-socta Madercnm,' ISni, p. 20. E. Doublcday, • AmiuU and Mag. of Nat. Ilist.' vol i. 1848, p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearan
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