30 BULLETIN 15 7, U. S. NATIONAL MUSEUM 



is extraordinary in view of the relative scarcity of the butterfly. 

 On the isolated willow bushes in the fields are many of the cater- 

 pillars of the viceroy {Basilarchia archippm) in every stage of 

 growth, while an examination of the sassafras and the tuliptrees 

 will disclose the caterpillars of the spicebush swallowtail {Papilio 

 froilus), known locally as " mellow bugs." 



The preceding sketch represents conditions that prevailed in the 

 middle of September, 1928- But the picture constantly is changing 

 and is never quite the same in different years. 



In the same fields at the same time of year in 1925 the orange 

 clover butterfly {C olios eurytheme) was very scarce, and only one 

 or two were to be seen during the course of an entire day. On the 

 other hand, the cabbage butterfly {Pieris rapae) was rather com- 

 mon, and the checkered white {Pierns protodice) occurred, though 

 in small numbers. The nicippe {Eurenia nicippe) was occasionally 

 seen, and the painted lady {Pyrameis cardui) was frequent on the 

 thistle flowers. This last seemed to be wholly absent from the 

 District in 1928. 



But the most extraordinary difference between 1925 and 1928 was 

 the great abundance in the former year and complete absence in the 

 latter of the large dark form of the common buckeye {Junonia 

 lavinia)^ the caterpillars of which were to be found in numbers on 

 the pink gerardia {Agalinis purpurea) . 



In the middle of September in 1926 the eubule {Phoebis eubule) 

 was here occasionally seen flying high and with great speed from 

 west to east, and we took specimens of the azure {Strymon tii-alhuTn) 

 and the gray {Strynion Tiielimis) hairstreaks. In that year also the 

 yellow swallowtail {Papilio glaucus) was very common. 



Earlier in the season in these fields and in the woods adjacent 

 several other butterflies are common. In May the pretty little orange 

 tip {AnthochaHs genutia) flutters about the open woods between 

 the fields and the canal, and in the open places in these woods and 

 especially along the roads are found the dusky skippers (species of 

 Thanaos and Thorytes). In June and July in these same woods the 

 wood nymph {N eonympha eurytus) is often seen (it is common in 

 some places). From the middle of June to the middle of July about 

 patches of white turtlehead {Chelone glabra) growing in a boggy 

 hollow and along a ditch in the open fields the turtlehead butterfly 

 {Euphydryas phaeton) formerly was very common, and its conspic- 

 uous caterpillars quite abundant. But in 1927 it had greatly de- 

 creased in numbers, and none were found in 1928 or 1929, though 

 it reappeared in 1930 and 1931. From the middle of July until 

 about the end of August the goggle eye {Gercyonis alope) is some- 

 times to be seen along the borders of the woods, but it is scarce and 

 very shy. In midsummer the red admiral {Pyrameis atalanta) was 



