BIRDS. 491 



metallic blue; in which respects this species approaches the 

 Java peacock. P. hardunckii possesses a peculiar top-knot, 

 which is also somewhat like that of the Java peacock. In 

 all the species the ocelli on the wings and tail are either 

 circular are oval, and consist of a beautiful, iridescent, 

 greenish-blue or greenish-purple disk with a black border. 

 This border in P. chinquis shades into brown, edged with 

 cream color, so that the ocellus is here surrounded with 

 variously shaded, though not bright, concentric zones. 

 The unusual length of the tail-coverts is another remark- 

 able character in Polyplectron; for in some of the species 

 they are half and in others two- thirds as long as the true 

 tail feathers. The tail-coverts are ocellated as in the 

 peacock. Thus the several species of Polyplectron mani- 

 festly make a graduated approach to the peacock in the 

 length of their tail-coverts, in the zoning of the ocelli, and 

 in some other characters. 



Notwithstanding this approach, the first species of Poly- 

 plectron which I examined almost made me give up the 

 search; for I found not only that the true tail-coverts, which 

 in the peacock are quite plain, were ornamented with ocelli, 

 but that the ocelli on all the feathers differed fundament- 

 ally from those of the peacock, in there being two on the 

 same feather (fig. 55), one on each side of the shaft. 

 Hence I concluded that the early progenitors of the pea- 

 cock could not have resembled a Polyplectron. But on 

 continuing my search I observed that in some of the spe- 

 cies the two ocelli stood very near each other; that in the 

 tail-feathers of P. hardioickii they touched each other ; 

 and finally that on the tail-coverts of this same species as 

 Avell as of P. malaccense (fig. 56) they were actually con- 

 fluent. As the central part alone is confluent, an indenta- 

 tion is left at both the upper and lower ends; and the sur- 

 rounding colored zones are likewise indented. A single 

 ocellus is thus formed on each tail-covert, though still 

 plainly betraying its double origin. These confluent ocelli 

 differ from the single ocelli of the peacock in having an 

 indentation at both ends instead of only at the lower or 

 basal end. 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. chinquis) they converge toward one 

 end; now the partial confluence of two convergent ocelli 



