BUTTEBPLIES OF THE DISTKICT OF COLUMBIA 115 



This butterfly is very fond of flowers, and is frequently seen on 

 goldenrod and other composites late in autumn. 



Seasons. — My dates for the variegated fritillary are June 2 and 

 16, July 24 (when five specimens were taken at Cabin John all 

 more or less worn), August 1, 3, 6, and 28, September 6, 17, 19, 20, 

 and 24, and October 13. There are probably three broods, one late in 

 May and early in June, the next in the last half of July and early 

 in August, and the third in the latter part of September. But in 

 regard to these we have no definite data for this region. 



Of the three specimens in the Schonborn collection, one, a female, 

 is dated September 2. 



Remarks. — Farther south the caterpillars of this butterfly are 

 sometimes destructive to pansies and violets. 



NOTE 



In addition to the species of Nymphalinae given in the foregoing 

 pages, the following might be expected to occur in this region : 



Vanessa milherti (see p. 244). 

 Vanessa j-albiim (see p. 245). 

 Polygonia faunus (see p. 245). 

 Dione vanillae (see p. 245). 



Argynnis atlantis (see p. 246). 

 Brentliis hellona (see p. 246). 

 Phyciodes nycteis (see p. 247). 

 Phyciodes carlota (see p. 247). 



Subfamily Danainae 



Genus DANAUS Linnaeus 



DANAUS PLEXIPPUS PLEXIPPUS (Linnaeus) 



Milkweed Butterfly ; Storm Fritillary ; Monarch ; Wanderer 

 Plate 6, Figure 4 ; Plate 58, Figures 1, 2 



Occurrence. — Usually frequent, though not very numerous, every- 

 where in open country — particularly in low meadows — over which it 

 is fairly evenly distributed; rarely abundant. Its numbers vary 

 more or less from year to year, and it appeared in great abundance 

 just after the middle of September, 1930. It is seen occasionally 

 in the Department of Agriculture and Smithsonian Institution 

 grounds, and in the parks and streets of Washington. 



Twenty years ago this species was very common and frequently 

 abundant in the District, but especially in the past 10 years its 

 numbers have greatly decreased so that it is no longer one of the 

 most familiar local insects. The decrease in its numbers has been 

 due to the wide extension of building and landscaping operations 

 in and about the District, for it is as common as ever not far away 

 in Maryland and in Virginia. 



