Caterpillar, etc.—The early stages are unknown.
This species has been confounded with A. atlantis, from which it is wholly distinct, being much smaller in size, the fore wings relatively broader, and the markings not so dark on the upper surface. It is found in Colorado and Montana, among the mountains.
(16) Argynnis columbia, Henry Edwards, Plate XIV, Fig. 3, ♂ (The Columbian Silver-spot).
Butterfly.—The male has the upper side of the fore wings pale reddish-fulvous. In the median band of both wings the spots do not flow together, but are separate and moderately heavy. The under side of the fore wings is pale fulvous, buff at the tip; spots silvered. The hind wings on the under side are light rusty-red, but little mottled with buff on the disk; the submarginal band is narrow, buff, and sometimes almost wholly obscured by the darker ground-color. The spots, which are small, are well silvered. The female is much lighter than the male, and, as usual, the dark lines are heavier than in that sex. The spots of the median band are bent and partly lanceolate, and the light spots of the outer border are whitish. Expanse, 2.25-2.50 inches.
Caterpillar, etc.—The early stages have not as yet been worked out.
This species, which is related to electa, may easily be distinguished from it by the pale marginal series of light spots, in the male, between the sagittate spots and the dark outer marginal lines, which latter are confluent, forming a solid dark outer border to the wing, while in electa they are separated by a narrow band of light-brown spots. The female is also much lighter and larger than in electa, as has been pointed out. The types which came from the Caribou mining region of British Columbia are in my possession, as are those of most of the other North American species of the genus.
(17) Argynnis hesperis, Edwards, Plate XII, Fig. 1, ♂; Fig. 2, ♁ (Hesperis).
Butterfly.—The male on the upper side of the wings is fulvous, shaded with dark fuscous for a short distance from the base. The black spots of the median band are rather broad, and seem to coalesce through dark markings along the nervules. The under side of the fore wings is pale ferruginous, tinged with a little buff at the tips, which, together with the outer margin, are somewhat heavily clouded with dark ferruginous. The under side of the hind wings is dark ferruginous, with a narrow buff submarginal band, which in some specimens is almost lost. The female is paler than the male in the ground-color of the upper side, the black markings are heavier, the marginal lines fuse, as do also the sagittate marginal markings, leaving the marginal spots between them, which are quite light in color, deeply bordered on all sides by black. The under side is like that of the male, but darker and richer in color. In neither sex are the light spots marked with silver; they are opaque, yellowish-white. Expanse, 2.25-2.40 inches.
Caterpillar, etc.—The life-history remains to be learned.
This insect is not uncommon among the mountains of Colorado.