INTRODUCTION. 25 



another of the protected group another mimicker more 

 nearly resembling it will represent it. We have one 

 remarkable example of this mimicry in our own country 

 in the resemblance of Basilarchia arcliippus to Anosia 

 plexippus. 



14. The Classification^ of Butterflies. 



The number of family groups into which butterflies 

 should be primarily divided has been variously given by 

 naturalists as from two to sixteen. Writers who have in- 

 sisted on any large number have, hoAvever, relied mainly 

 upon single and relatively unimportant characters, mostly 

 drawn from the neuration of the wings of the imago, and 

 almost ignoring the earlier stages of the insects. Those 

 who have paid serious attention to the latter and have re- 

 garded all parts of the structure have generally considered 

 the number as from four to six. In the present work they 

 are regarded as but four in number, called Skippers (Hes- 

 peridae). Typical Butterflies (Papilionid^e), Gossamer- 

 winged Butterflies (Lycaenidae), and Brush-footed Butter- 

 flies (Nymphalidae). 



If we examine these d liferent groups with regard to 

 their interrelationship it is plain that the Skippers show 

 by far the greatest and most numerous points of resem- 

 blance to the moths; and if we look to the sum of the 

 characters of each as regards their departure from the char- 

 acteristics of the lower Lepidoptera, we shall see that they 

 unquestionably fall into the order in which they are here 

 placed. In addition to this we shall find two very distinct 

 parallel series in structure and transformations which fol- 

 low precisely the same course, each independent of the 

 other, each pointing out the lines along which develop- 

 ment has proceeded and thus indicating a natural classifi- 

 cation. 



