When figured side by side with the other Fritillaries, this species looks distinct enough from any of them;
but it has been several times confounded with small specimens of Adippe and with Euphrosyne, and its capture has thereupon been erroneously published; but this must have been the effect of a description imperfectly written or read. It will be observed that the form of the front wings differs in this from the rest of the Fritillaries, the outer margin being concave in its outline. The inner corner of the hind wings also is more sharply angular.
Above, the colouring of the wings is similar to that of the others of the genus, tawny-brown and black. Beneath, the front wing has a group of silver spots near the tip, the ground colour of the hind wing is yellowish, and the silver spots are proportionately larger than in the other species; near the margin of the hind wing, and parallel with its edge, are seven dark-brown spots with silver centres.
The caterpillar is brown, striped with white, and yellowish tint; head, legs, and thorns, tawny coloured. It feeds on the wild heartsease, also on sainfoin and borage.
The chrysalis is tinted with dull-green and brown, and spotted with gold.
The butterfly is said to be double-brooded—one brood appearing in June, the other in September. The most likely places in which to look for it are clover fields in the south of England, and more especially on the south-east coast. Though still classed among the rarest of British butterflies, it has been found in a great many localities. It has been taken at Brighton; Shoreham; Eastbourne; Dover; Margate; Ashford; Chatham; Exeter; Bristol; Harleston, near Norwich; Colchester; Lavenham; Peterborough.
THE PEARL-BORDERED FRITILLARY. (Argynnis Euphrosyne.)