Genus Erebia Dalman (the Alpines)
Rather small butterflies, dark in color, with eye-spots on the wings, most numerous on the under side. Veins of fore wing thickened at base; lower radial in some cases projected inwardly into the cell at point of origin. Outer margin of both wings evenly rounded. Egg subconical, ribbed, the ribs often intersecting each other. Larva with globular head, body tapering backward, last segment bifurcate. Chrysalis convex dorsally and ventrally, humped on thorax, produced at head, light brown or ashen gray.
The genus is arctic and confined to the far north, or to the summits of high mountains, which have an arctic climate. There are many species in the northern hemisphere, of which we select two for representation.
(1) Erebia discoidalis Kirby, Plate LXVI, Fig. 1, ♂ (The Red-streaked Alpine).
Easily distinguished from all other species in our fauna by the plain dark wings streaked on the costa and suffused over the outer three fourths of the middle of the fore wings with dark red or maroon. Expanse 1.75-2.00 inches.
Habitat region of Hudson Bay, thence westward to Alaska and southward among snowy peaks of British Columbia. Probably found on high mountains of Idaho and Montana.
(2) Erebia epipsodea Butler, Plate LXVI, Fig. 2, ♂ (The Common Alpine).
The upper side is shown in our cut; the under side repeats the markings of the upper side more or less clearly, and besides has on the hind wing a broad, curved, median, blackish band. Expanse 1.75-2.10 inches.
Ranges from the alpine summits of New Mexico northward at suitable elevations to Alaska, where it is common.