. The descent of man, and selection in relation to sex. Evolution (Biology); Sexual selection in animals; Sexual dimorphism (Animals); Sex differences; Human beings. Chap. XIV.] GRADATION OF CHARACTER, 137 toward the left-Land upper corner, the feather being held erect, in the position a b c in which it is here drawn. Beneath this thickened part there is on the surface of the ball an oblique almost pure-white mark whicli shades ofi downward into a pale-leaden hue, and this into yellow- ish and brown tints, which insensibly be- come darker and dark- er toward the lower part of the ball. It is t
. The descent of man, and selection in relation to sex. Evolution (Biology); Sexual selection in animals; Sexual dimorphism (Animals); Sex differences; Human beings. Chap. XIV.] GRADATION OF CHARACTER, 137 toward the left-Land upper corner, the feather being held erect, in the position a b c in which it is here drawn. Beneath this thickened part there is on the surface of the ball an oblique almost pure-white mark whicli shades ofi downward into a pale-leaden hue, and this into yellow- ish and brown tints, which insensibly be- come darker and dark- er toward the lower part of the ball. It is this shading, which gives so admirably the effect of light shining on a convex surface. If one of the balls be examined, it will be seen that the loAver part is of a browner lint oiirl iflxr Fig. 56.—Part of Secondary winsr-reather of imt ana is maiSlinctiy ^^.^^^ pheasanf, showing two. « anrl b, per- HPnfiTntpfl \\\r o piir-eprl feet ocelli. A, B, C, dark stripes run- Sepai area Oy a CUrveCl ^^^^^ obliquely down, each to an ocellus. oblique line from the [Much of the web on both sides, especially to . the left of the shaft, has been cut off]- upper part, which is yellower and more leaden; this oblique line runs at right angles to the longer axis of the wliite patch of light, and indeed of all the shading; but this difference in the tints, which cannot of course be shown in the woodcut, does not in the least interfere with the perfect shading of the ball.^^ *s When the Argus pheasant displays his wing-feathers hke a great fan, those nearest to the body stand more upright than the outer ones,. 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, D. Appleton and company
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Keywords: ., bookcentury1800, bookdecade1870, booksubj, booksubjecthumanbeings
