204 THE STUDY OF INSECTS. 



selection. The classification of animals and plants should not be 

 merely the assorting of them into convenient pigeon-holes, but 

 a serious study of their blood-relationships. 



The following synopsis will serve to show what we believe to be 

 the relations of the principal divisions of the order. Following this 

 synopsis there is a table for use in classifying specimens. 



SYNOPSIS OF THE LEP1D0PTERA. 

 (See page 207 for a table for determining specimens.) 



A. The Jugate Lepidoptera. — Moths in which the two wings of 



each side are united by zjitgum (Fig. 238, J), p. 214. 



Suborder JuGATVE. 



B. The Swifts or Macrojugatce, p. 215 Family Hepialid^e. 



BB. The Little- wing Jugates or Microjugatce, p. 216. 



Family MicropterygiDjE. 

 AA. The Frenate Lepidoptera. — Moths, skippers, and butterflies 



in which the two wings of each side are united by a. frenulum (Fig. 



237./) or by its substitute, a large humeral angle of the hind wing 



(Fig. 241), p. 201 Suborder Frenatae. 



B. The Generalized Frenatae. — Moths that are supposed to 

 retain more nearly than any other Frenatae the form of the primi- 

 tive Frenatae, those that were the first to appear on earth. In 

 these generalized moths the wings approach the typical form; 

 the base of vein V of one or both pairs of wings is preserved 

 throughout a considerable part at least of the discal cell ; and 

 the anal veins are well preserved, there being two or three in 

 the fore wing and three in the hind wing. The frenulum is 

 usually well preserved. 



The Flannel-moths, p. 218 Family Megalopygid^e. 



The Bag-worm Moths, p. 219 Family Psychid/E. 



The Carpenter-moths, p. 221 Family CossiD^E. 



The Slug-caterpillar Moths, p. 223 Family Eucleid^e. 



The Smoky-moths, p. 226 Family Pyromorphid^e. 



BB. The Specialized Frenatae. — Moths, skippers, and butter 

 flies that depart more widely than do the Generalized Frenatr: 

 from the primitive type of Lepidoptera, being more highly modi- 

 fied for special conditions of existence. An indication of the 

 specialized condition of these insects is the modified form of the 

 wings. In nearly all the base of vein V has been lost and the 

 branches of this vein joined to veins III and VII. 



