The Classification of Butterflies 



Varieties. — A still further subdivision is in some cases recog- 

 nized as necessary. A species which has a wide range over an 

 extensive territory may vary in different parts of the territory 

 within which it is found. The butterflies of certain common 

 European species are found also in Japan and Corea, but, as a 

 rule, they are much larger in the latter countries than they are in 

 Europe, and in some cases more brightly colored. Naturalists 

 have therefore distinguished the Asiatic from the European form 

 by giving the former what is known as a varietal name. Similar 

 differences occur among butterflies on the continent of North 

 America. The great yellow and black-barred swallowtail but- 

 terfly known as Papilio turnus occurs from Florida to Alaska. 

 But the specimens from Alaska are always much smaller than those 

 from other regions, and have a very dwarfed appearance. This 

 dwarfed form constitutes what is known as a local race, or variety, 

 of the species. The members of a species which occur upon an 

 island frequently differ in marked respects from specimens which 

 occur upon the adjacent mainland. By insulation and the process 

 of through-breeding the creature has come to acquire characteris- 

 tics which separate it in a marked degree from the closely allied 

 continental form, and yet not sufficiently to justify us in treating 

 it as a distinct species. It represents what is known as an insu- 

 lar race, or variety, and we give it therefore a varietal name. 

 Naturalists also distinguish between seasonal, dimorphic, me- 

 lanic, and albino forms. Names descriptive or designatory of 

 these forms are frequently applied to them. All of this will be- 

 come plainer in the course of the study of the succeeding pages, 

 and in the effort to classify specimens which the student will 

 make. 



Sex.— The designation of the sex is important in the case of 

 all well-ordered collections of zoological specimens. As a mea- 

 sure of convenience, the male is usually indicated by the sign of 

 Mars, S , while the female is indicated by the sign of Venus, ? . 

 The inscription, " Argynnis Diana, 6," therefore means that 

 the specimen is a male of Argynnis Diana, and the inscription, 

 "Argynnis Diana, ?," means that the specimen is a female of 

 the same species. These signs are invariably employed by nat- 

 uralists to mark the sexes. 



The Division of Butterflies into Families. — Without attempting 

 to go deeply into questions of classification at the present point, 



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