174 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



Order Lepidoptera. Lepidoptera, or moths and butterflies, 

 are the insects most favored of collectors and nature lovers. 

 The beautiful color patterns, the graceful flight and dainty 

 flower-haunting habits and the interesting metamorphosis 

 during their development make them very attractive, while 

 the comparative ease with which the various species may be 

 determined and the large number of popular as well as more 

 technical books about them, make the moths and butterflies, 

 among all the insects, most collected and studied. 



About 7000 species are known in North America, and except 

 for a few kinds with wingless females and a few other clear- 

 winged kinds which have a superficial likeness to wasps and 

 bees, all the species may be readily recognized as moths or 

 butterflies by the complete coating of tiny scales on the four 

 wings both above and below. It is on these scales that the 

 colors and patterns of the moths and butterflies depend. The 

 scales are very small, varying from 1/350 to 1/30 of an inch 

 in length and from the thickness of a fine hair to 1/60 of an 

 inch in breadth. They are arranged in more or less regular 

 rows, which overlap each other so that a shingle-like covering 

 over the wing is produced. On a large butterfly the total 

 number of scales on all the wings may number more than a 

 million. Each scale is really a tiny flattened membranous sac 

 with a short stem which is held in a little pit or pocket in the 

 wing membrane. All the scales are finely and regularly 

 striated from base to tip, and most of them contain a number 

 of small pigment granules. The colors are produced both 

 by the pigment and by the complicated reflections caused by 

 the striated and laminated structure of the scales. On the 

 latter condition depend the irridescent and metallic colors, 

 such as the changing blues and greens, while on the presence 

 of the pigment depend the fixed brown, reddish and yellow 

 colors. The wings themselves are large and membranous 

 and supported by a few strong veins. The fore wings are 

 longer and narrower in proportion to their length than the 

 hind wings, this condition being particularly emphasized 

 among the swift-flying species, such as the sphinx-moths. 



The mouth-parts of all the Lepidoptera, except a few 



