Genus Brenthis 
base and the hind wings on the inner half being deeply obscured 
with fuscous. The markings are quite heavy. The fore wings 
on the under side are very pale fulvous, yellowish at the tip, 
mottled with ferruginous. The hind wings are ferruginous on 
the under side, mottled with yellow. The spots are quite large, 
consisting of lines and dashes, and a marginal row of small lunu- 
late spots, pale yellow or white, slightly silvered. Expanse, 
1.50 inch. 
This butterfly is circumpolar, being found in Norway, Lap- 
land, northern Russia, and Siberia, through Alaska, British 
America, and Labrador, occurring also upon the highest peaks 
of the Rocky Mountains as far south as Colorado. 
(8) Brenthis polaris, Boisduval, Plate XV, Fig. 1 1 , <3; 
Fig. 12, $, under side (The Polar Fritillary). 
Butterfly .—-The upper side dull fulvous; the markings on the 
inner half of the wings are confluent, and lost in the brownish 
vestiture which obscures this portion of the wing. The outer 
median area is defined by irregular zigzag spots which flow to¬ 
gether. Beyond these the submarginal row of small black spots 
stands out distinctly upon the lighter ground-color of the wings. 
The outer margin is marked by black spots at the end of the 
nervules, on the fore wings somewhat widely separated, on the 
hind wings narrowly separated by the lighter ground-color. On 
the under side the wings are fulvous, with a marginal row of 
white checkerings on both wings. The hind wing is deeply 
mottled with ferruginous, on which the lighter white markings 
stand forth very conspicuously. Expanse, $, 1.50 inch; 
1.50-2.00 inches. 
Early Stages .— Unknown. 
This butterfly has been found in Labrador, Greenland, and 
other portions of arctic America, as far north as latitude 8i° 52'. 
(9) Brenthis frigga,Thunberg, Plate XV, Fig. 13, 6 ; Fig. 14, 
$ , lower side (Frigga). 
Butterfly , $.— On the upper side this butterfly somewhat 
closely resembles polaris , but the markings are not so compact — 
more diffuse. The fore wings at the base and the hind wings 
on the inner two thirds are heavily obscured with brown. The 
outer margins are more heavily shaded with blackish-brown than 
in B. polaris. On the under side the wings are quite differently 
marked. The fore v/ings are fulvous, shaded with brown at the 
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