. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings -- Origin. Chap. XIV. Birds—Gradation of Characters. 435 shaft to one of the ocelli. The spots are generally elongated in a line transverse to the row in which they stand. They often become confluent, either in the line of the row—and then they form a longitudinal stripe—or transversely, that is, with the spots in the adjoining rows, and then they form transverse stripes. A spot sometimes breaks up into smaller spots, which still stand in their proper places. It will be convenient first
. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings -- Origin. Chap. XIV. Birds—Gradation of Characters. 435 shaft to one of the ocelli. The spots are generally elongated in a line transverse to the row in which they stand. They often become confluent, either in the line of the row—and then they form a longitudinal stripe—or transversely, that is, with the spots in the adjoining rows, and then they form transverse stripes. A spot sometimes breaks up into smaller spots, which still stand in their proper places. It will be convenient first to describe a per- fect ball - and - socket ocellus. This consists of an intensely black, circular ring, surround- ing a space shaded so as exactly to resemble a ball. The figure here given has been ad- mirably drawn by Mr. Ford and well engraved, but a woodcut cannot exhibit the exquisite shading of the original. The ring is almost always slightly broken or interrupted (see fig. 57) at a point in the upper half, a little to the right of, and above the white shade on the enclosed ball; it is also sometimes broken to- wards the base on the right hand. These little breaks have an important meaning. The ring is always much thickened, with the edges ill-defined towards the left- hand upper corner, the feather being held erect, in the posi- tion in which it is here drawn. Beneath this thickened part there is on the surface of the ball an oblique almost pure-white mark, which shades off downwards into a pale-leaden hue, and this into yellowish and brown tints, which insensibly become. Fie:. 57. Part of secondary wing-feather of Argus-, pheasant, shewing two perfect ocelli, a and b A, B, C, D, &c, are dark stripes running obliquely down, each to an ocellus. [Much of the web on both sid^s, esp daily to the left of the shaft, has been cut off.]. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colorat
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Keywords: ., boo, bookcentury1800, bookdecade1880, booksubjectnaturalselection
