THE BUTTERFLIES OF THE DISTRICT OF COLUMBIA 



Bv AUSTIN H. CLARK, 



Curator. Diinsion of Rchinodcrms, U. S. Nalioiial Museum 



One hundred and nine years have passed since Mr. David Baillie 

 Warden iml)Hshed in Paris a short list of the Ijuttertlies of the District 

 of Cohimhia, and (hn-ing that time only scattered notices of a few 

 species have appeared. 



With the transformation of the District from a region largely of 

 woods and open fields to an area of city hlocks and suhurhan dwell- 

 ings and estates there has come a change in the local fauna. Some 

 species, found especially in scruliby pastures, have almost disappeared, 

 while others, living chiefly on common weeds thriving in unkept city 

 lots and suburban gardens, are increasing in numbers. Others have 

 disappeared through inability to meet the competition of new comers. 



In order to construct a picture of the butterfly fauna as it exists 

 at the i^-esent time extensive field investigations have been carried 

 out in the District and vicinity. These investigations had to do 

 especially with the local characteristics of the butterflies, the varieties 

 of each found in this area, their local occurrence, and their habits. 



Eighty-seven kinds of butterflies are now known from the District 

 and its more or less immediate vicinity. But of these only a few are 

 really common and many are very local, found only in widely separated 

 places. Some are only accidental visitors. One, the cloudless sulphur 

 (CatopsUia sciuicc), which is not so very rare, is represented only 

 by adventurous males which stray here in late summer. No females 

 ever have been seen in this locality. 



Two of our common summer butterflies, the milkweed butterfly 

 (Daiiaiis iiiciiippc) and the painted lady {Cyiitliia carcliii), seem 

 unable to survive our winter. Each spring wandering females enter 

 the region and lay their eggs on their respective food plants in the low 

 ground near the river. The young from these, appearing in July, 

 scatter everywhere, and the next generation, in late August and 

 September, usually is abundant. When the cool weather comes the 

 butterflies hide away in some safe retreat in which they die. 



Two other butterflies, the buckeye (Junonia cocna) and the red 

 admiral {Cynthia atalauta), in the local bogs wherever their food 

 plants grow, produce a large and richly colored form of more or less 



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