BUTTERFLIES OF THE DISTRICT OF COLUMBIA 159 



descending, the female then coming down more leisurely and in a 

 different direction. Often a rising pair will be joined by a second 

 male and sometimes by a third or even by a fourth, so that four or 

 five butterflies are fluttering about together. In this case the female 

 never rises for more than about 10 feet. 



In mated pairs the male always carries the female in flight. I 

 once caught a white female that was carrying a yellow male. But on 

 examination the male proved to be dead, probably having been killed 

 by a phymatid bug or a crab spider. 



This butterfly is very fond of flowers, and its preference for yellow 

 flowers often has been noticed. It prefers to feed on flowers at 

 about the level of the grass tops. In this region the butterflyweed 

 {Asclepias tuberosa) provides the flowers seemingly most attractive, 

 and in a grassy field a dozen or more may be seen upon a single plant 

 in company with as many pearl crescents {Phydodes tharos) and a 

 few tailed blues {Everes comyntas). Red clover is the flower next 

 preferred, and after that the flowers of small leguminous plants in 

 general. Late in summer it is fond of the flowers of the goldenrod, 

 of the thistles, and of the asters, though preferring the flowers of 

 small leguminous plants if it can find them. 



If a cloud obscures the sun these butterflies at once seek a place to 

 rest. Their first choice is a yellowed clover leaf, or a yellowed leaf 

 of any kind. In gardens they are very partial to yellowed leaves on 

 privet hedges. 



The males are particularly fond of sucking moisture from mud, 

 and on muddy places they gather in little companies of from 3 or 4 

 to a dozen or 15 or more. Almost invariably these companies include 

 more or fewer of the lisa {Eurema lisa) , which sometimes are in the 

 majority. 



Like all the social mud-loving pierids, the yellow clover butterfly is 

 easily decoyed by dropping dead butterflies or even bits of yellow 

 paper on the mud. 



The males of this species are very attentive to the smaller females 

 of the orange clover {Collas eurytheme) ^ though the orange males 

 take little notice of the yellow females. Occasionally the males of 

 the two species will flutter about each other for an instant, though 

 they soon separate. 



Seasons. — The yellow clover butterfly appears usually shortly be- 

 fore the middle of April and becomes common in the last half of 

 the month and in the first half of May, but the individuals in the 

 first brood are never very numerous. In the last half of May the 

 butterflies become very scarce and all the individuals are worn ; they 

 disappear entirely before the end of the month. Early in the second 

 week in June occasional fresh males are seen, which mark the advent 

 of a new brood ; by the middle of the month they have become com- 



