THE BUTTERFLIES OF VIRGINIA 



By AUSTIN H. CLARK 

 Curator, Division of Echinoderms, U. S. National Museum 



Just because a certain kind of butterfly happens to be common in 

 a given region it does not necessarily follow that it is really at home 

 there. It may be a visitor. Regular summer visitors are rather numer- 

 ous among Virginia's butterflies, including some of the commonest 

 among them. All of these come from the south. Straggling individuals 

 in the spring wander north from the Carolinas or from Tennessee and 

 lay their eggs on the proper food plants. By the end of the season 

 their descendents may be abundant over the whole State. 



On looking over some thousands of records, we find that the least 

 sulphur (Terias lisa) , one of the very commonest butterflies in late 

 summer and autumn, has never been found in Virginia before the 

 end of May, when the second brood begins to appear. It is, therefore, 

 only a summer visitor. All of the millions of individuals in the State 

 die during the winter. Another butterfly very common all over Vir- 

 ginia in late summer is the buckeye or peacock (Precis coenia). For 

 this also our earliest records are in the latter part of May. But by the 

 middle of July the buckeye is a familiar insect everywhere. These 

 two are samples of the regular summer visitors from the south, butter- 

 flies that every year become abundant in Virginia, only to be killed out 

 at the end of the season by the winter's cold. 



Some visitors come from more distant regions. As an example, 

 there is the painted lady (Vanessa carclui). This is the most widely 

 distributed of butterflies. It is found all over Africa and over very 

 nearly all of Europe and Asia, excepting the plains of India. In North 

 America it has been captured in Alaska and in the region of Hudson 

 Strait. It reaches Iceland more frequently than any other butterfly. 

 Yet in North America it is not known to be a permanent resident 

 anywhere north of Mexico. From its home in Mexico it is constantly 

 wandering northward, establishing itself temporarily all over the 

 United States, and even in Canada. 



Other visitors from the southwest find their way to Virginia. Some 

 are very unusual, like the Ontario hairstreak (Strymoii Ontario) and 

 the early hairstreak (Erora la eta), but others are more familiar. Once 

 in a while wholly unexpected visitors turn up, usually from the south, 



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