. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings; Sexual selection in animals; Sexual dimorphism (Animals); Sex differences. imEOTL 843 leiiiura.* ±a certain Ciircnlionidse and CaraWdaef the parts are completely reversed in position, for the rasps are seated on the interior surface of the elytra^, near their apices, or along their outer margins, and the edges of the abdominal segments serve as the scrapers. In Pelobius Hermanm one of Dytiscidse oi* water-beetles) a strong ridge runs parallel a ad near to the sutural margin of the elyt
. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings; Sexual selection in animals; Sexual dimorphism (Animals); Sex differences. imEOTL 843 leiiiura.* ±a certain Ciircnlionidse and CaraWdaef the parts are completely reversed in position, for the rasps are seated on the interior surface of the elytra^, near their apices, or along their outer margins, and the edges of the abdominal segments serve as the scrapers. In Pelobius Hermanm one of Dytiscidse oi* water-beetles) a strong ridge runs parallel a ad near to the sutural margin of the elytra and is crossed by ribs, coarse in the middle part, but becoming graduallj finer at both ends, especially at the apper end; when this insect is held ijider w^ter or in the air a stridulating noise is produced by the extreme horny margin of the abdomen being scraped against the rasps. In a great num- ber of long-horned beetles (Longicornia) the ofgans are situated quite otherwise, the rasp being on the meso-thorax, which is rubbed against the pro-thorax. Landois counted 238 very fine ribs on the rasp of Cerambyx heros. Many Lamellicorns have the power of stridulating, and the organs differ greatly in position. Some species stridulate very loudly, so that when Mr. F. Smith caught a Trox sabulosus, a gamekeeper who stood by thought he had caught a mouse; but I failed to discover the proper organs in this beetle. In Geotrupes and Typhoeus a narrow ridge runs obliquely across (r, fig. 26) the coxa of each hind leg (having in G. stercorcmtis 84 ribs), which is scraped by a specially project- {rfiS.* ^'"^^^^^ ing part of one of the abdominal segments. In the nearly allied Copris hmaris an excessively narrow fine rasp runs along the sutural margin of the elytra with another short rasp near the basal outer margin; but in some other Coprini the rasp is seated, according to * Scliiodte, translated in "Annals and Mag. of Nat ^ilst.," vol. xx^ 1867, p. 37. f Westring has d
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Keywords: ., bookcentury1800, bookdecade1870, booksubjecthumanbeings, bookyear
