([Plate X]. fig. 4.)
This very common insect is considerably smaller than any of the preceding species, though small specimens of the last sometimes do not much exceed it in size. The upper surface is lively orange-brown, with black markings. Beneath, the hind wing is mapped out with black lines into various irregular spaces, all of which are filled with tints of dull yellow, ochreous, or reddish orange; excepting a row of silver spots on the border, one silver spot in the centre of the wing, and one triangular one close to the root of the wing.
The caterpillar is black, with white lines; and the pro-legs red. It feeds on various species of viola.
The butterfly appears first in May, and there is another brood in autumn, about August. It frequents woods and hedgerows, being met with most profusely in the south; but its range is extended into Scotland. In Ireland I believe it is unknown.
THE SMALL PEARL-BORDERED FRITILLARY. (Argynnis Selene.)
([Plate XI]. fig. 1.)
This butterfly, which is very nearly related to the last, often so closely resembles it in the marking of the upper surface, that even practised eyes are sometimes at a loss to distinguish the two, without a reference to the under side; for on this side do the real distinctive marks lie, and chiefly on the hind wing. In addition to the silver border and central spots of Euphrosyne, this species has several other silvery or pearly patches distributed over the hind wing; and the reddish-orange colour adjoining the silver border in Euphrosyne is exchanged for dark chestnut-brown in Selene. In average size the two insects differ very slightly, though the name of this expresses an inferior size.
The caterpillar much resembles that of the last, and feeds on violet-leaves.