PIERINAE: KURY.MUS EURYTIIK.MK. 1133 



"dancing a nuptial pas lie deux with a conij)anion : tlioy twirled lii<,di into the 

 air beyond reat'li, iiut soon separated and came to earth again, when one 

 was captured." 



Gcddes says that this is one ot'the liveliest of the Euryini, the tbrin eri- 

 phyle especially being "almost impossible to catch on the wing from its zig- 

 zag movement in Hying, and its long flights, often Hying high in the air." 

 From the few times I have seen this insect in flight I shoidd consider it 

 somewhat but not greatly more active than E. philodicc. Others habitu- 

 ated to seeing only the latter have been similarly im[)res8ed as Gcddes. 

 Thus Pearson, of Montreal, "saw something like a Hash of orange light 

 Hit past him" and described its movements thus : "Away it was Hying like 

 a ray of sunlight. Hitting from Hower to Hower, resting only for about the 

 smallest conceivable portion of time." So, too, according to Mr. Bethune, 

 itsliabits are similar to those of the previous species, but its flight is more 

 rapid ; it scarcely ever rests for more than an instant, and can only be cap- 

 tured after a long and exciting chase. 



Polymorphism. A\'ith the possible exception of Cyanirispseudargiolus, 

 this butterfly is tlie most polymorphic yet discovered, the different forms 

 assumed in diHerent localities and at different seasons of the year having been 

 described four or five times as distinct species ; and inasmuch as the species 

 extends over a vast extent of country both latitudinally and longitudinally, 

 its life history is modified to a considerable extent, and a commingling 

 of forms ensues which is often very puzzling to understand. Moreover, 

 while in the north the direct sequence of activities is interfered vvitii by 

 the winter, in the extreme south, on the other hand, by the summer with its 

 blazing sun, which dries np the food plant so completely that were it not 

 for the lethargic powers of the catei-pillar, the species must become extinct. 



It is difHcidt to present a picture of so complicated a life history and a 

 polymorphism combined. We shall perhaps get a clearer view of their 

 relations, if we begin our explanation with an account of the condition of 

 things in the extreme south, following Mr. Boll, who first pointed out the 

 direct relationship of several of the forms previously considered distinct 

 species. In his paper read to the Association of German Naturalists at 

 Hamburg in 187(5, Mr. Boll states that in the region where he had resided 

 in northern Texas the cycle of changes begins with the appearance of the 

 butterfly upon the wing, generally in November, directly after the more 

 abundant rains of October iiave caused the leaves of the food plant of the 

 caterpillar again to flourish. During the warm days of winter, fresh exam- 

 ples are frequently found and it flics imintcrruptedly until tlie end of June, 

 is most connnon in March, in May becomes more rare, and by the end of 

 June vanishes altogether. Before the emergence of the last butterflies 

 from the chrysalis, tiie running Buff^tlo clover which forms the food plant 

 of the caterpillar dies to the root. The earliest btitterflies which appear up 



