The descent of man, and selection in relation to sex . characters, to thepeacock. Notwithstanding this approach, the first species ofPolyplectron which I happened to examine almost mademe give up the search; for I found not only that thetrue tail-feathers, which in the peacock are quite plain,were ornamented with ocelli, but that the ocelli onall the feathers differed fundamentallv from those ofthe peacock, in there being two on the same feather,(fig. 54), one on each side of the shaft. Hence I Chap. XIV. GKADATION OF CHAllACTERS. 139 concluded that the early progenitors of the peacock could n
The descent of man, and selection in relation to sex . characters, to thepeacock. Notwithstanding this approach, the first species ofPolyplectron which I happened to examine almost mademe give up the search; for I found not only that thetrue tail-feathers, which in the peacock are quite plain,were ornamented with ocelli, but that the ocelli onall the feathers differed fundamentallv from those ofthe peacock, in there being two on the same feather,(fig. 54), one on each side of the shaft. Hence I Chap. XIV. GKADATION OF CHAllACTERS. 139 concluded that the early progenitors of the peacock could not have resembled in any degree a Polyplectron. But on continuing my search, I observed that in some of the species the two ocelli stood very near each other; that in the tail-feathers of P. HardwicMi they touched each other; and, finally, that in the tail-coverts of this same species as well as of P. ona- laccense (fig. 55) they were actually confluent. As the central part alone is confluent, an indentation is left at both the upper and lower ends;. and the surrounding coloured Fig. 54. Part of a tail-covert of Poly-plectron chinquis, with the two ocelliof nat. size. zones are likewise indented. A single ocellus is thus formed on each tail-covert, though still plainly betraying its double orioin. These con- fluent ocelli differ from the single ocelli of the peacock in having an indentation at both ends, instead of at the lower or basal end alone. The explanation, however, of this difference is not difficult; in some species of Polyplectron the two oval ocelli on the same feather stand parallel to each other; in other species (as in P. cliinquis) they converge towards one end; now the partial confluence of two convergent ocelli would manifestly leave a much
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Keywords: ., boo, bookcentury1800, bookdecade1870, booksubjectnaturalselection
