BUTTERFLIES OF THE DISTRICT OF COLUMBIA 193 



While this butterfly is sometimes seen fluttering in a leisurely 

 manner over muddy spots in roads and barnyards, as a rule it keeps 

 rather strictly to the fields and meadows where only, apparently, it 

 feels secure. 



The males are more active and more restless than the females, 

 and have a more rapid and irregular and also somewhat higher 

 flight. When feeding they usually, though not always, keep their 

 wings in motion, while the females more frequently rest with par- 

 tially extended wings. As in the case of the yellow swallowtail, 

 the males are prone to wander and may even be rather frequent 

 in areas where females are seldom or never to be found. 



Broods. — In the vicinity of Washington this butterfly is two 

 brooded, the first brood appearing in the second week of May and 

 continuing to emerge into early June, becoming scarce after the 

 middle of June and disappearing toward the middle of July. The 

 males appear a week or more before the females. The individuals 

 of the second brood begin to appear early in July, but do not become 

 abundant until the end of the month; they continue on the wing 

 until the middle of September, and occasional individuals may be 

 found until the middle of October. 



There is less difference between the butterflies of the first and 

 the later brood than is the case with the other local swallowtails. 

 There is no appreciable difference in size, and some, at least, of the 

 several varietal forms seem to be relatively as common in one brood 

 as in the other. 



Local varietal forms. — Within the District the males of the pars- 

 nip swallowtail occur in three main types, one of which is abundant, 

 one fairly common, and one rather rare. Between these three types 

 intergrades are found. 



In the most abundant form (pi. 41, fig. 1) the spots of the inner 

 row of the fore wings are triangular with the bases outward, close 

 together, and the apices pointing inward. The lowermost spot is 

 elongated with the ends rounded, and that just above is large, thickly 

 crescentic, or trapezoidal with the outer border notched. There is 

 commonly a narrow yellow dash across the end of the cell in the 

 fore wings; while this is often absent it is occasionally broad and 

 conspicuous. 



On the hind wings the inner series of yellow markings takes the 

 form of a yellow band crossed by black veins, the black scaling on 

 the vein delimiting the end of the cell being especially broad. This 

 band begins with a spot, which varies from about as broad as long 

 to only half as broad as long, the outer edge of which lies just under, 

 or just within, the inner end of the lowest spot on the fore wing. 

 The inner border of the band runs in a practically straight line to 



