144 



SEXUAL SELECTION : BIRDS. 



Part II. 



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. bQ stripe 

 A runs to ocellus a; B runs to ocellus h ; stripe C is 

 broken in the upper part, and runs down to the next 

 succeeding ocellus, not represented in the woodcut; I) 

 to the next lower one, and so with the stripes E and F. 



Lastly, the several ocelli 

 are separated from each 

 other by a pale surface 

 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 bodv, is marked 

 like the other feathers, 

 witli oblique, longitudi- 

 nal, rather irregular, rows 

 of spots. The lowest spot, 

 or that nearest the shaft, 

 in the five lower rows (ex- 

 cluding the basal row) is 

 a little laro;er than the 

 other spots in the same row, and a little more elon- 



Fig. 57. Basal part of the Secondary wing- 

 feather, nearest to the bod^'. 



SO that the shading cf 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 

 experien<-ed eye of an artist, asserts (' Field,' Newspaper, May 28, 1870, 

 p. 457) that this is the case ; but after carefully examining two mountt d 

 specimens (the proj^er feathers from one having been given to me by 

 Mr. Gould for more accurate comparison) I cannot perceive that this 

 acme of perfection in the shading has beeu attained ; nor can others 

 to whom I have shewn these feathers recognise the fact. 



