HOW TO KNOW THE BUTTERFLIES 



short, but grow very wide as compared with their 

 length. Every gradation in form can be found 

 from the ordinary hairlike form, which occurs 

 most abundantly upon the body, to the short and 

 broad scale, which is best seen upon the wings 

 (Fig. 10). 



The use of the scales on the wings is to 

 strengthen them. We thus see that the wings 



of these insects are fur- 

 nished with much fewer 

 cross-veins than are the 

 wings of similar size in 

 other orders. A sec- 

 ondary use of these 

 scales is that of orna- 

 mentation; for the 

 beautiful colors and 

 markings of these in- 

 sects are due entirely to 

 the scales, and are destroyed when the scales are 

 removed. Upon the body, legs, and other ap- 

 pendages, the scales and hairs doubtless serve to 

 protect the insect, being a sort of armor. 



In the wings of males of many butterflies 

 there are scent glands that open through scales. 

 It should be stated in this connection that scales, 

 like other hairs of insects, are hollow and well 



iS 



Fig. ii. — Part of the wing of a 

 butterfly, greatly magnified. 



