PREFACE 



During the 24 years which have passed since I first became a more 

 or less continuous resident of the District of Cohimbia, the great 

 extension of the city of Washington, and especially the development 

 of suburban areas within and adjacent to the District, have brought 

 about very considerable changes in the faunal balance. 



These changes have been evident to everyone with even a casual 

 interest in butterflies. Several species have not been seen in the 

 District for many years, while others have disappeared quite recently. 

 Many that presumably were once common are now very rare or 

 merely casual. Several others occur only in isolated colonies in 

 very limited areas of boggy ground which are certain to be filled in 

 within the next few years, resulting in the elimination of all traces 

 of the butterflies. 



Yet this region is a singularly interesting one, a sort of meeting 

 ground for northern and southern, mountain and coastal plain 

 species or forms. Indeed, one single species {Cercyonis cdope) occurs 

 in no less than three distinct forms, a dark northern coastal {^nari- 

 fima), a northern interior (alope), and a very pale southern moun- 

 tain form, while there is a possibility, judging from individuals seen 

 but not caught, that even a fourth form, the southern coastal 

 (pegala), is also found here. 



In view of all this, it has seemed worth while to present a some- 

 what detailed account of the local fauna as I and others have known 

 it in the past and as it is to-day. 



The seasons of the various species and the habits of the indi- 

 viduals differ more or less, and often to a considerable degree, in 

 different areas within their range. Much attention has therefore 

 been devoted to this phase of the study of the local butterflies. 

 Many species have been raised, but in most cases no information 

 worthy of record was obtained. 



While the observations upon which this account of the District 

 butterflies is based have extended over many years, it has not been 

 possible to devote much time to intensive study. Usually during 

 the season I spent a part of each Sunday in the field, and in the 

 past five years also devoted occasional week days to the work. 



During the course of these studies I have had the constant cooper- 

 ation of Dr. L. O. Howard, Dr. William Schaus, Dr. William T. M. 



ui 



