Its Display in Courtship. 257 



Prom my own observation I can fully confirm the state- 

 ment of Mr. Wood, namely, that the ocelli are so shaded as 

 to represent the light coming from above when the wings are 

 expanded as the bird is displaying itself. In the engraving 

 the ocelli of the secondary feathers nearest the tail have the 

 light side shown nearest the top of the feather, whereas on 

 the first and second secondaries, those which are held nearest 

 the ground and most horizontally, the light is next the shaft 

 of the feather. 



The mode in which these ocelli have been produced has 

 been the subject of a very elaborate and ingenious disquisition 

 by Darwin (" Descent of Man," vol. ii., p. 141), to which I 

 would refer those of my readers who desire to enter more 

 deeply into the subject ; but the following remarks on the 

 characteristics of the feathers and their employment by the 

 male are so graphic that I need make no apology for quoting 

 them (vol. ii., p. 91) : — 



" The immensely developed secondary wing feathers, which 

 are confined to the male, are ornamented with a row of from 

 twenty to twenty-three ocelli, each above an inch in diameter. 

 The feathers are also elegantly marked with obhque dark stripes 

 and rows of spots, hke those on the skin of a tiger and leopard 

 combined. The ocelU are so beautifully shaded that they 

 stand out like a ball lying loosely within a socket. But when 

 I looked at the specimen in the British Museum, which is 

 mounted with the wings expanded and trailing downwards, 

 I was greatly disappointed, for the ocelli appeared flat or even 

 concave. Mr. Gould, however, soon made the case clear 

 to me, for he had made a drawing of a male whilst he was 

 displaying himself. At such times the long secondary feathers 

 in both wings are vertically erected and expanded, and these, 

 together with the enormously elongated tail feathers, made a 

 grand semicircular upright fan. Now as soon as the wing 

 feathers are held in this position, and the hght shines on them 

 from above, the full effect of the shading comes out, and each 

 ocellus at once resembles the ornament called a ball-and- 



