202 ENTOMOLOGY 



son in other words, may be seasonally dimorphic, trimorphic 

 or polymorphic. 



Thus Polygonia interrogations has two forms, fabricii and 

 umbrosa, which differ not only in coloration, but even in the 

 form of the wings and the genitalia. In New England fabricii 

 hibernates and produces umbrosa, as a rule, while umbrosa 

 usually yields fabricii. 



The little blue butterfly, Cyaniris pseudargiolus (Fig. 231), 

 is polymorphic to a remarkable degree. In the high latitudes 

 of Canada, a single brood (In da) occurs. About Boston, the 

 same spring brood appears, but under two forms : an earlier 

 variety (luda), which is small, with large black markings 



Cyaniris pseudargiolus; A, form luda; B, -ciolacea; C, pseudargiolus proper. 

 Natural size. 



beneath; and a later variety (violacea), which is typically 

 larger, with smaller black spots, though it varies into the form 

 luda. Finally, in summer, a third form (pseudargiolus 

 proper) appears, as the product of luda or else the joint prod- 

 uct of luda and violacea, and this is still larger, but the black 

 spots are now faint. In the warm South, the spring form is 

 violacea, but while some of the males are blue, others are 

 melanic, as just mentioned a dimorphic condition which does 

 not occur in the North. Violacea then produces pseudargi- 

 olus, in which, however, all the males are blue. 



Iphiclides ajax (Fig. 232) is another polymorphic butterfly 

 whose life history is complex. The three principal varieties 

 of this species, known respectively as marccllus, telamonides 

 and ajax, differ not only in coloration, but also in size and 

 form; marcellns appears first, in spring; telamonides appears 



