. The descent of man : and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings. 43^ The Descent of Man. Part II. darker and darker towards 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 sepa- rated by a curved oblique 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 indeed of
. The descent of man : and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings. 43^ The Descent of Man. Part II. darker and darker towards 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 sepa- rated by a curved oblique 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 indeed of all the shading; but this difference in colour, which cannot of course be shewn in the woodcut, does not in the least interfere with the perfect shading of the ball. It should be particularly observed 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 tig. 57 stripe A runs to ocellus a; B runs to ocellus h ; stripe C is broken in the upper part, and runs down to the next succeeding ocellus, not represented in the wood- cut ; D to the next lower one, and zo w'ith the strijDes E and F. Lastly, the several ocelli are separated from each other by a pale surface bear- ing irregular black marks. I will next describe the other extreme of the series, namely, the first trace of an ocellus. The short se- condary wing-feather (fig. 58), nearest to the body, is marked like the other feathers, with oblique, lon- gitudinal, rather irregular, rows of very dark spots. The basal spot, or that near- est the shaft, in the five lower rows (excluding the lowest one) is a little larger than the other spots of the same row, and a little more elon- gated in a transverse direc- tion. It differs also from the other spots by being bordered on its upper side with some dull fulvous shading. But this spot is not in any way more remarkable than those on the plumage of many birds, and mig
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Keywords: ., bookcentury1800, bookdecade1870, booksubjecthumanbeings, bookyear
