BUTTERFLIES OP THE DISTRICT OF COLUMBIA 207 



teristic of the flight of most of the species of this group of butterflies. 

 They pass with amazing speed at a height of about 4 feet above the 

 ground, darting at every insect near their path, and especially at 

 others of their kind. When two meet they whirl about each other 

 for a second or two, when one suddenly makes off, pursued for a 

 short distance by the other. Sometimes three, or even four, will 

 whirl about together, passing back and forth like a living tornado 

 over a considerable space, then separating as suddenly as they met. 



Their great speed renders them exceedingly difficult to catch, for 

 one is no sooner seen than it has passed by. But they have two 

 peculiarities that serve to overcome this difficulty. One is that 

 individuals flying back and forth mostly travel in parallel lines in 

 a relatively narrow belt, so that from a positon in this flyway they 

 are easily intercepted. Another is that the flight of any individual 

 is never of long duration. It quickly tires and suddenly drops down 

 to rest on the topmost leaf of some conspicuous plant higher than 

 those about it, or on the summit of a dead weed stalk. From this 

 point of vantage it makes occasional vicious darts at insects passing 

 by. When the butterfly is resting the wings are partially expanded, 

 the hind wings making a greater angle with each other than the 

 fore wings. 



The females are rather inactive, and are much less widely dis- 

 tributed than the males. Their flight is low and leisurely, with a 

 feeble skipping, and is always short. 



On cloudy or cool days the males lose their energy and indulge 

 merely in short flights, which have the skipping character of the 

 flight of related species, though this is never very strongly marked. 

 At such times the flight is low, never more than a few inches above 

 the grass tops, and by no means swift, being practically identical 

 with the flight of the females. 



Individuals of both sexes are very fond of sunning themselves on 

 leaves or weed stalks with their wings expanded to the horizontal 

 and the fore wings drawn well back. Solitary males are some- 

 times seen sucking moisture from mud with their wings partly 

 raised in the resting position. 



Seasons. — I have taken this butterfly on July 24, frequently from 

 the last week in August until toward the end of September, then 

 in decreasing numbers until the middle of October. It is most 

 abundant in the middle of September. 



It is undoubtedly triple brooded here, the first brood, not yet 

 reported here, probably flying from the end of April until early in 

 June or perhaps later, the second from late in June until early in 

 August, and the third and most abundant from late in August until 

 well into October. Individuals are probably to be found, in varying 

 numbers, throughout the summer. 



