214 



WING SCALES OF LEPIDOPTERA. 



The wings of the butterflies and moths are composed 

 of a double membrane, itself transparent and colourless, 

 but covered on both the upper and under surfaces with a 

 great number of minute feathers or scales. It is to the 

 colour and arrangement of the scales that the brilliancy 

 and variety of the wings are due. The colours are owing 

 sometimes to pigments in the scales and sometimes proceed 

 from the refraction of the light from the striations and 

 spots on the scales, from their formation and arrangement, 

 or from fine hairs which are found amoncrst them. 



I 6 



Gen M'e/uontuf IG*" '>fe/ir>n:a 



Sb ntrclahnu!. I ''|> '^ordali , 



Fig. 13. 



The scales are of great variety in shape and size, 

 arrangement and quantity, but arc generally very numerous, 

 in some cases more than 100,000 being found in one square 

 inch of wing-surface It is not surprising therefore that the 

 combination of such minute detail with every colour, 



