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 ocelli 

 of 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 



Fig. 55. Part of a tail-covert of Poly- 

 plectron malaccense, with tlie two 

 ocelli, partially confluent, of nat. size. 



