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THE AMERICAN MUSEUM JOURNAL 



tion. Then, too, only three Basilarchia 

 disippus were discovered, but certain 

 other migrants, ahnost certainly an- 

 other species of Basilarchia, would seem 

 to indicate that the presence of disippus 

 was not accidental. Moreover, although 

 Thecia was clearly identified only on 

 September 16, it was certainly present 

 on one or two other occasions. 



It is highly significant, too, that the 

 winter phase of the common "clouded 

 sulphur" (Colias philodice) is so little 

 noted. This is probably accounted for 

 by the fact that this phase, whatever its 

 nature, is passed, in many cases, in 

 some region outside our immediate lati- 

 tude. The presence of the common 

 cabbage butterfly (Pieris rapce), also, 

 is very interesting, for, being a Eu- 

 ropean importation, it recalls the many 

 reports Avhich exist in Old World litera- 

 ture regarding the extensive migrations 

 of its close relative, the larger cabbage 

 butterfly, Pieris hrassicce. In some 

 cases the numbers involved have been 

 so great as to give the appearance of a 

 drifting snowstorm blowing over the 

 water or moving steadily in one direc- 

 tion over the land. Indeed, one writer 

 has noted that these butterflies seem 

 able to alight on the water surface for 

 a moment to rest, and then to rise again 

 and pursue their interrupted flight in 

 the same general direction as before. 



The "great sulphur" (Catopsilia 

 eubule) in eastward flight is somewhat 

 puzzling, as is the record also of Pieris 

 rapce on September 8. For that this 

 eastward flight of Catopsilia is quite 

 habitual at Long Beach, seems evident 



from an earlier observation on this 

 same beach, October 19, 1915, when a 

 single individual passed east. Yet its 

 habitual course along the Connecticut 

 shore is west, as shown by an extensive 

 flight during September 33, 33, and 34, 

 189-1, and by recent September observa- 

 tions by the writer. In addition to this 

 movement, however, Mr. William T. 

 Davis believes there is a late summer 

 movement from the south, which would 

 account for these eastward flights on 

 Long Island. 



Finally, after considering various ex- 

 planations which might be offered, it is 

 difficult to avoid the conclusion that, 

 whatever their outcome, many of these 

 flights are as truly seasonal and migra- 

 tory as are those of birds. It is an 

 interesting fact, moreover, that all of 

 these species of butterflies and dragon 

 flies have a wide distribution into the 

 Southern States, so there is no impos- 

 sibility in the conception of a prolonged 

 movement for some species other than 

 the "monarch." The exact limits of 

 travel for each, however, and the ques- 

 tion of a spring return for certain of 

 the longer-lived species, can be deter- 

 mined only by experiments of marking 

 the butterflies as they pass and tracing 

 them in their later course along the 

 coast. 



Our records give certain evidence that 

 such interesting secrets exist, and that 

 some region or regions to the south of 

 us undoubtedly contain the answer to 

 problems, hitherto neglected, in the 

 lives of some of our commonest, most 

 familiar Initterflies. 



