. The descent of man, and selection in relation to sex. Evolution (Biology); Sexual selection in animals; Sexual dimorphism (Animals); Sex differences; Human beings. 346 SEXUAL SELECTION. [Part IL In the last and third Family, namely, the Acridiidse or o-rasshoppcrs, the stridulation is produced in a very diftercnt nuuiner, and is not so shrill, according to Dr. Scudder as in the preceding Families. The inner surface of the femur (fig. 13, r) is furnished with a longitudinal row of minute, elegant, lancet-shaped, elastic teeth, from 85 to 93 in number;" and these are scraped across the sh
. The descent of man, and selection in relation to sex. Evolution (Biology); Sexual selection in animals; Sexual dimorphism (Animals); Sex differences; Human beings. 346 SEXUAL SELECTION. [Part IL In the last and third Family, namely, the Acridiidse or o-rasshoppcrs, the stridulation is produced in a very diftercnt nuuiner, and is not so shrill, according to Dr. Scudder as in the preceding Families. The inner surface of the femur (fig. 13, r) is furnished with a longitudinal row of minute, elegant, lancet-shaped, elastic teeth, from 85 to 93 in number;" and these are scraped across the sharp, projecting nervures on the wing-covers, which are thus made to vibrate and resound. Harris" says that when one of the males begins to play, he first "bends the shank of the hind-leg beneath the thigh, where it is lodged in a furrow designed to receive it, and then draws the leg briskly up and down. He does not play both fiddles together, but alternately first upon one and then on the ; Fig. 13.—Hind-lcs^ofStenobothnispratorum: T„ ,vio,i-tr cnp^^pa thp bnsp r, the strululating ridiic; loWer fl-ure, "^ many SpCCieS tnc oase the teeth, forming: the ridge, much mag- f]-,p. ohdonipn is hol- nilied (from Landois). ^ OT. int auuoiiitu it> uui lowed out into a great cavity which is believed to act as a resounding-board. In Pneumora (fig. 14), a South African genus belonging to this same family, we meet with a new and remarkable modifi- cation : in the males a small notched ridge projects ob- liquely from each side of the abdomen, against which the hind femora are rubbed.'° As the male is furnished with the Platiiphyllum concavum, " when captured, makes a feeble grating noise by shuffling her wing-covers ; 31 Landois, ibid. s. 113. 38 'Insects of New England,' 1842, p. 133. 39 Westwood, ' Modem Classification,' vol. i. p. Please note that these images are extracted from scanned page images that may have been digitally e
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Keywords: ., bookcentury1800, bookdecade1870, booksubj, booksubjecthumanbeings
