. 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. ^ (? Fig. 23. Bledius taurus, magnified. Left-hand figure, male; right-hand figure, female. the principle of compensation, owing to the development of the large horns and projections on the lower surface; and as these are contined to the males, the rudiments of the upper horns on the females would not have been thus obliterated. The cases hitherto given refer to the Lamellicorns^ but the males of some few other
. 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. ^ (? Fig. 23. Bledius taurus, magnified. Left-hand figure, male; right-hand figure, female. the principle of compensation, owing to the development of the large horns and projections on the lower surface; and as these are contined to the males, the rudiments of the upper horns on the females would not have been thus obliterated. The cases hitherto given refer to the Lamellicorns^ but the males of some few other beetles, belonging to two widely distinct groups, namely, the Curculionidae and Staphylinidae, are furnished with horns—in the former on the lower surface of the body,* in the latter on the upper surface of the head and thorax. In the Staphylinidae, the horns of the males are extraordinarily variable in the same species, just as we have seen with the Lamellicorns. In Siagonium we have a case of dimorphism, for the males can be divided into two sects, differing greatly in the size of their bodies and in the development of their horns, with- out intermediate gradations. In a species of Bledius (fig. 33), also belonging to the Staphylinidae, Prof. Westwood ^l^irby and Speace, *'Introduct. Entomolog.,'* ypl. iii, p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Darwin, Charles, 1809-1882. New York : A. L. Burt
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Keywords: ., bookcentury1800, bookdecade1870, booksubjecthumanbeings, bookyear
