32 
Psyche 
[March 
great numbers over wide areas not permanently inhabited 
by it and its complete disappearance during the succeeding 
winter are readily explained if we recognize the existence 
of a “wet” form comparable to that of Junonia ccena and 
Cynthia atalanta. 
The “dry” females in the spring are very active and 
wander in every direction, scattering their eggs over a wide 
extent of territory. If they are numerous and if conditions 
are favorable they will become dispersed over regions far 
beyond the area where they passed the winter. 
This species differs from the two just considered in being 
normally an inhabitant of semi-arid regions. Under the con- 
ditions found in the District and in the greater part of New 
England the young from over-wintered females develop into 
the large and brilliant “wet” form, which appears in July. 
The young of these summer butterflies, appearing on the 
wing in late August and September, are of the same form as 
their parents. But in the District spring individuals, which 
are not at all common and are only to be seen in the low 
ground near the river, are always of the “dry” form. 
So apparently the reason for the irregular appearance 
of this butterfly is that in most of the area from which it is 
known its caterpillars develop into a form unable to survive 
the winter and its occurrence therefore is dependent on 
regular, more or less irregular, or occasional incursions of 
overwintered females from elsewhere. 
Polygonia interrogationis and P. comma . — The foregoing in- 
terpretation of the forms of Junonia coena , Cynthia atalanta 
and C. cardui , and analogy with Polygonia c-album cognata and 
P. c-a. agnicula of the Himalayan region and P. c-a. hamigera 
of Japan, Corea and northern China, suggest a correspond- 
ing interpretation of the seasonal forms of Polygonia interro- 
gationis and P. comma. 
In the District of Columbia the light form of P. inter- 
rogationis is variable in color, some of the individuals being 
much darker than others, especially in the female. In P . 
comma the light form seems usually to be darker than in 
New England with more extensive infuscation of the hind 
wings, some individuals, indeed, being almost as dark as the 
dark form. In both species the shape of the wings is con- 
stantly different in the two forms, so that such indications 
of intergradation as occur are wholly in the color. 
