. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings -- Origin. Fig. 23. Bledius taurus, magnified. Left-hand figure, male; right-hand figure female. states that, " male specimens can be found in the same locality * in which the central horn of the thorax is very large, but the " horns of the head quite rudimental; and others, in which the "thoracic horn is much shorter, whilst the protuberances on " the head are ;67 Here we apparently have a case of compensation, which throws light on that just given of the
. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings -- Origin. Fig. 23. Bledius taurus, magnified. Left-hand figure, male; right-hand figure female. states that, " male specimens can be found in the same locality * in which the central horn of the thorax is very large, but the " horns of the head quite rudimental; and others, in which the "thoracic horn is much shorter, whilst the protuberances on " the head are ;67 Here we apparently have a case of compensation, which throws light on that just given of the supposed loss of the upper horns by the males of Onitis. Law of Battle.—Some male beetles, which seem ill-fitted for fighting, nevertheless engage in conflicts for the possession of the females. Mr. Wallace68 saw two males of Leptorhynchus angustntus, a linear beetle with a much elongated rostrum, " fighting for a female, who stood close by busy at her boring. " They pushed at each other with their rostra, and clawed and •* thumped, apparently in the greatest ; The smaller male, however, " soon ran away, acknowledging himself ; In some few cases male beetles are well adapted for fighting, by possessing great toothed mandibles, much larger than those of the females. This is the case with the "-common stag-beetle (Lucanns cervus), the males of which emerge from the pupal state about a week before the other sex, so that several may often be seen pursuing the same female. At this season they 66 Kirby and Spence, 'Iutroduct. gnnium in an intermediate condi- Entomolog.' vol. iii. p. 329. tion, so that the dimorphism is not 67 ' Modern Classification of In- strict. sects,' vol. i. p. 172: Siagonium, 68 'The Malay Archipelago,'vol. p. 172. In the British Museum I ii. 1869, p. 276. Riley, Sixth ' Report noticed one male specimen of Sia- on insects of Missouri,'1874, p. Please note that these images are extracted from scanned page i
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Keywords: ., boo, bookcentury1800, bookdecade1880, booksubjectnaturalselection
