. The descent of man, and selection in relation to sex. Evolution; Heredity; Human beings; Natural selection. 456 THE DESCENT OF MAN. [PAST It the enclosed ball; it is also sometimes broken toward the base on the right hand. These little breaks have an important meaning. The ring is always much thickened, with the edges ill-defined toward the left-hand upper corner, the feather toeing held erect, in the position A R^^C^ in which it is here drawn. Beneath this thickened part there is on the sur- face of the bail an obliciue almost pure-white mark, which shades oft' down- ward into a pale-leaden
. The descent of man, and selection in relation to sex. Evolution; Heredity; Human beings; Natural selection. 456 THE DESCENT OF MAN. [PAST It the enclosed ball; it is also sometimes broken toward the base on the right hand. These little breaks have an important meaning. The ring is always much thickened, with the edges ill-defined toward the left-hand upper corner, the feather toeing held erect, in the position A R^^C^ in which it is here drawn. Beneath this thickened part there is on the sur- face of the bail an obliciue almost pure-white mark, which shades oft' down- ward into a pale-leaden hue, and this into yel- lowish and brown tints, which insensibly become darker and darker 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 lower part is of a brown tint and is indistinctly separated by a curved ob- lique line from the upper part, which is yellower and more leaden; this curved oblique line runs at right angles to the longer axis of the white patch of light, and in- deed of all the shading; but this difference in color, which cannot, of course, be shown in a woodcut, does not in the least interfere with the perfect shading of the ball. It should be particularly ob- served that each ocellus stands in obvious connection either with a dark stripe, or with a longitudinal row of dark spots, for both occur indifferently on the same feather. Thus in fig. 57 stripe A runs to ocellus ^ / B runs to ocellus b ; stripe C is broken in jtbe upper part and runs down to the next succeeding Fig. 57.—Part of secondary wing-feafher of Argus pheasant, showing two perfect ocelli, a and b. A. B, C. O, are dark stripes running obliquely down, Kich to an ocellus. [Much of the web on both sides, especially to the left of the shaft, has been cut off.]. Please note that these images are extracted from scanned page images that may have b
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Keywords: ., bookcentury1800, bookdecade1870, booksubjecthumanbeings, bookyear
