Vlil INTRODUCTORY. 



than clubbed. Day-flying moths, especially the bright-coloured 

 ones, might be mistaken for butterflies by the uninitiated, but 

 in all these the horns will be found not at all butterfly-like. 



Although varieties of the species will be referred to in the 

 descriptive portion of the book, a few general remarks on 

 variation in butterflies may here be made. All kinds are liable 

 to vary in tint or in the markings, sometimes in both. Such 

 variation, in the more or less constant species especially, is 

 perhaps only trivial and therefore hardly attracts attention. In 

 a good many kinds variation is often of a very pronounced 

 character, and is then almost certain to obtain notice. Except 

 in a few instances, where the aberration is of an unusual kind, 

 it is possible to obtain all the intermediate stages, or gradations, 

 between the ordinary form of a species and its most extreme 

 variety. A series of such connecting links in the variation of a 

 species is of greater interest, and higher educational value, than 

 one in which the extremes alone have a place. 



In those kinds of butterflies that attain the perfect state twice 

 in the year, the individuals composing the first flight are some- 

 what different in marking from those of the second flight. Such 

 . species as the large and small whites exhibit this kind of varia- 

 tion, which is termed seasonal dimorphism. The males of 

 some species, as for example the Common Blue and the Orange- 

 tip, differ from the females in colour ; this is known as sexual 

 dimorphism. The Silver- Washed Fritillary, which has two 

 forms of the female, one brown like the male, the other green 

 or greenish in colour, is a good example of dimorphism con- 

 fined to one sex. Gynandrous specimens, sometimes called 

 " Hermaphrodites," are those which exhibit both male and 

 female coloration, or other wing characters ; when one side 

 is entirely male and the other side entirely female, the 

 gynandromorphism would be described as complete. 



The ornamentation on the under side of a butterfly differs 

 from that of the upper side, and is found to assimilate or 



