152 BULLETIN 15 7, U. S. NATIONAL MUSEUM 



grounds, and was occasionally seen throughout the city. Ernest 

 Shoemaker wrote me that he found it very common on the Eastern 

 Branch from September 19 to 25, and this was the first season he 

 had taken it in nearly 50 years' collecting. 



In 1928 it was first taken on June 24 and was very common from 

 the first of July onward, although in this year it was considerably 

 less abundant than in 1927. Its numbers were equal to one-third or 

 one-fourth the numbers of G . philoSice. On October 6 and 7 a 

 careful count was made at Cabin John, and it was found to be just 

 one-fifth as numerous as C. philodice. 



In 1929 it was taken as early as May 12, when two males were 

 seen and one captured. It disappeared in the last week in May, 

 but fresh individuals appeared in the second week in June. By the 

 end of June it had become abundant, and it remained abundant, its 

 numbers being, in some places at least, equal to the numbers of 

 G. philodice. 



In 1930 it was noticed on April 27, and both sexes were common on 

 May 4, when they outnumbered the corresponding sexes of G. philo- 

 dice. It disappeared toward the end of May, but reappeared in 

 the middle of the second week in June when a male was seen at 

 the intersection of Seventh Street and Constitution Avenue. At 

 the end of the summer it far outnumbered G. philodice. 



Summing up the history of this butterfly in the District, we may 

 say that prior to 1926 it occurred only in very small numbers late 

 in summer and in autumn. The earliest recorded date is September 

 6, and most of the individuals were taken or seen after the middle of 

 September. This would indicate that the individuals found in the 

 District were the young of a few intruders of the midsummer brood. 

 In 1926 it was for the first time numerous. It was first taken on 

 August 27. Apparently in this year a large number of the young 

 of the intruders survived. But the intruders could not have been 

 very many, as none were seen in the course of very intensive combing 

 of the fields in July. In 1927 and 1928 it appeared in June and 

 early in July. In this year the earliest individuals were evidently 

 the young of intruders of the spring brood, the later individuals 

 in this year representing a second instead of a first local generation. 

 In 1929 and 1930 it appeared late in April and early in May. As 

 the earliest examples were perfectly fresh they could not have come 

 in from outside, but must have hibernated here, the species having 

 now become a permanent resident. 



Whether it will continue as a permanent resident, or will decrease 

 to its former status as a rather scarce late-summer intruder, or will 

 eventually entirely disappear, remains to be seen. 



Entry hito the District. — The entry of this butterfly into the 

 District is simply the local phase of its extension into the region east 



