Archive image from page 151 of The descent of man, and. The descent of man, and selection in relation to sex descentofmansel02darw Year: 1871 138 SEXUAL SELECTION: BIRDS. [Pakt II. It shoukl be i)articiilarly observed that each ocellus stands in obvious connection with a dark stripe, or row of dark spots, lor both occur indiflerently on the same feather. Thus ill ViiT. 50 stripe A runs to ocellus a ; B inins to ocellus h; stripe C is broken in the upper part and runs do\l to the next succeeding ocellus, not rejiresented in the wood- cut ; D to the next lower one, and so with the stripes E and
Archive image from page 151 of The descent of man, and. The descent of man, and selection in relation to sex descentofmansel02darw Year: 1871 138 SEXUAL SELECTION: BIRDS. [Pakt II. It shoukl be i)articiilarly observed that each ocellus stands in obvious connection with a dark stripe, or row of dark spots, lor both occur indiflerently on the same feather. Thus ill ViiT. 50 stripe A runs to ocellus a ; B inins to ocellus h; stripe C is broken in the upper part and runs do\l to the next succeeding ocellus, not rejiresented in the wood- cut ; D to the next lower one, and so with the stripes E and F. Lastly, the several ocelli are separated from each oth- er by a pale sui-f:ice bearing irregular black marks. I will next describe the other extreme of the series, namely, the first trace of an ocellus. The short secondary wing- feather (Fig. 57), nearest to the body, is marked, like the other feathers, Avith oblique, longitudi- \ --â ' nal, rather irregular, rows of sjtots. The lowest spot, or that nearest the shaft, in the five lower rows (ex- \ I eluding the basal row) is a little larger than the Fig. .'JT.âBaenl part of the Secondary , '. , winsi-fcatlicr, nearest to the body. OtiKT SpotS in the Same SO that the shading of the ball-and-socket ocelli ought to be slightly different on the different feathers, in order to bring out their full effect, relatively to the incidence of the light. Mr. T. W. Wood, who has the eye of an artist, asserts ('Field,' newspaper. May 28, 1870, p. 4r)7) that this is the case; but after carefully examining two mounted specimens (the proper feathers from one having been given to me by Mr. (Jould for more accurate comparison) I cannot perceive that this acme of l)erfcction in the shading has been attained ; nor can others to whom I have shown these feathers recognize the fact.
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Keywords: 1800, 1870, 1871, archive, book, bookauthor, bookcentury, bookdecade, bookpublisher, booksubject, bookyear, darwin_charles_1809_1882, drawing, evolution_biology_, historical, history, human_beings, illustration, image, new_york_d_appleton_and_company, page, picture, print, reference, sex_differences, sexual_dimorphism_animals_, sexual_selection_in_animals, vintage
