CiiAP. XIV. 



GRADATION OF CHAKACTEES. 



143 



the feather being held erect, in the position in which it 

 is here drawn. Be- 

 neath this thickened 

 part there is on the 

 surface of the ball an 

 oblique almost pure- 

 white mark, w^hich 

 shades off downwards 

 into a pale-leaden hue, 

 and this into yellow- 

 ish and brown tints, 

 which insensibly le- 

 come darker and dark- 

 er towards the louer 

 part of the ball. It 

 is this shading which 

 gives so admirably the 

 effect of lio-ht shinino- 

 on a convex surface. 

 If one of the balls be 

 examined, it will be 

 seen that the lovver 

 part is of a browner 

 tint and is indistinctly 

 separated by a curved 



oblique line from the [Much of the web on both s=dps. especially to the 

 , . , . left of ihe shaft, has been cut off.] 



upper part, which is 



yellower and more leaden ; this oblique line runs at 

 riofht ano-les to the lonofcr axis of the white patch of 

 light, and indeed of all the shading; but this difference 

 in the tints, which cannot of course be shewn in the 

 woodcut, does not in the least interfere with the perfect 

 shading of the ball.*^ It should be particularly ob- 



Fig. 56. Part of Secondary wing-feather of Argus 

 pheasant, shewing two, a and b, perfect ocelli. 

 A, B, C, &c., dark stripes running oblitiuely down, 

 each to an ocellus. 



•*^ When the Argus pheasant displays his wing-feathers like a great 

 fan, those nearest to the body stand more upright than the outer ones, 



