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Show 14.4 SEXUAL SELECTION: BIRDS. l'AI:T H. served that each ocellus stands in obvious connection with a dark stripe, or row of dark spots, for both occur indifferently on the same feather. Thus in fig. 56 stripe A runs to ocellus a; B runs to ocellus b; stripe 0 is broken in the upper part, and runs down to the next succeeding ocellus, not represented in the woodcut; D to the next lower one, and so with the stripes E and F. Lastly, the several ocelli arc separated from each other by a palo surface bearing irregular black marks: I will next describe the other extreme of the series, narn ely the first trace of an ocellus. The short secondary wingfeather (fig. 57), nearest to the body, is marked like the other feathers, with oblique, longitudinal, rather irregular, rows of spots. The lowest spot, or that nearest the shaft, in the five lo¥ver rows (exFig. 57. nasal part of the Secondary wing- cludinoO' the basal row) is feather, nearc~t to the body. a little larger than the other spots in the same row, and a little mor~ elon-so that the shading cf tho ball-and-socket ocelli ought to be slightly diflercnt on the ditlcrcnt feathers, in order to bring out their full effect, relatively to the incidence of the light. Mr. T. W. Wood, who bas the expcricnr!ed eye of an artist, asserts(' Field,' Newspaper, May 28, 1870, p. 4:57) thn.t this is tho case; but after carefully examining two mounted ~pccim o ns (the proper feathers from one having been given to me by Mr. Gould for more accurate comparison) I cannot perceive 1hat this acme of perfection in the shading has been attained ; nor can others to whom I have shewn these featl~ ors recognise the fact. <.'HAP. XIV. GRADATION OF CHARACTERS. 145 gated in a transverse direction. 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 it~y way m_ore remarkable than those on the plumage of many bu·ds, and might easily be quite overlooked. The next higher spot in each row does not differ at aU from the upper ones in the same row, althotwh in the following series it becomes, as we shall see, g~eatly modified. The larger spots occupy exactly the same relative position on this feather as those occupied by the perfect ocelli ·on the longer wing-feathers. By looking to the next two or three succeedin()' sec~ndary wing-feathers, an absolutely insensible gra~ datwn can be traced from one of the above-described lower spots, together with the next higher one in the same row, to a curious ornament, which cannot be called an ocellus, and which I will name, from the want of a .better term, an" elliptic grnament." These are shewn in the accompanying figure (fig. 58). vVe here see ·several oblique rows, A, B, 0, D (see the lettered diagram), &c., of dark spots of the usual character. Each row of spots runs down to and is connected with one of the elliptic ornaments, in exactly the same manner as each stripe in fig. 56 runs down to, and is connected with, one of th~ ball-and-socket ocelli. Looking to any one ro~, for mstanc~, B, the lowest spot or mark (b) is thicker a.nd considerably longer than the upper spots, ~n~ has Its left e~tremity pointed and curved upwards. This black mark IS abruptly bordered on it· upper side by a rather broad space of richly-shaded tints l>e()'innin()' . l ' 0 0 ~Vlt I a. n~rrow brown zone, which passes into orange, n.nd th1s mto a pale leaden tint, with the end towards the shaft ~uch paler. This mark corresponds in every respect with the htrger, shaded spot, described in tho last paragnwh (fig. 57), but is more highly deve- VOL. II. L |