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in which red occurs. It will be noted also that violet seldom 

 occurs in these birds : this is undoubtedly due to the fact that 

 the author, in description, has confused the colours violet and 

 purple, using the term purple in very many cases to describe 

 that which is obviously violet. This failure is common and is 

 doubtless due to a want of appreciation of the colour violet 

 owing to its rarity, and the great predominance of purple, in 



r 40 



30 



10 



B R 



W Bl Br 



- 40 



30 



10 



Bl 



Br 



G B R£SK»* O *•«•••« Y W 



Nymphalinae (48) 

 Diagram No. 10. 



the arts. Thus the consideration of these birds fulfils the pre- 

 diction. The Nectariniidas also support the contention that 

 yellow is not a conspicuous colour except by reason of its lumi- 

 nosity, for in a great many species the males have bright yellow 

 at the throat and breast, with dorsal and lateral areas of red, 

 blue, and violet ; in females the red, blue, and violet areas are 

 replaced by green, but the yellow at the throat and breast 



