404 
THE STUDY OF INSECTS. 
wings, and by the presence of a whitish spot on both fore 
and hind wings, near the apex, and between two larger 
black patches. On the lower surface of the hind wings 
there is a small L-shaped silvery bar. This species occurs 
Fig. 477 .—Eugonia j-album. 
throughout Canada and the northern portion of the United 
States east of the Rocky Mountains. 
Polygonia (Pol-y-go'ni-a).—The butterflies of this genus 
resemble the preceding species in having a metallic spot on 
the lower surface of the hind wings, but differ in having the 
inner margin of the fore wings roundly notched beyond the 
middle. Nearly a dozen species occur in this country. 
These differ principally in the coloring and markings of the 
under surface of the hind wings. The following are some 
of the more common ones :— 
The Green Comma, Polygonia faunas (P. fau'nus).—The 
silvery mark of the hind wings is usually in the form of 
a C or a G, the ends being more or less expanded (Plate VI, 
Fig. 2), but sometimes it is reduced to the form of an L. 
The lower surface of the wings is more greatly variegated 
than in any other species of this genus; and there is a larger 
amount of green on this surface than in any other of the 
eastern species, there being two nearly complete rows of 
green spots on the outer third of each wing. 
The larva feeds upon black birch, willow, currant, and 
