The Small Pearl-bordered Fritillary (Argynnis Selene)
This butterfly differs from the last one referred to in having a rather deeper colour on the upper side, and heavier black markings on the outer margin of the hind wings. The female is slightly more orange in tint, and has a series of pale spots on the outer margin of each wing. On the under side the red markings are browner in tint, and there are more silvery spots on the hind wings. Variation in colour and marking is similar to that mentioned under the Pearl-bordered. On Plate 66 a white spotted female and a specimen with the hind wings clouded with black are represented. These are rather uncommon aberrations. The life-history of this species is figured on Plate 62.
The egg is at first greenish, then yellowish, and afterwards greyish, and then becoming blackish towards the hollowed top. The ribs seem to be eighteen or twenty in number; laid in June or July on plants of dog-violet. On emerging from the egg the young caterpillar devours most of the shell. It is then of a pale olive colour with brownish warts, from each of which there is a pale and rather long jointed bristle; the head is black. The full-grown caterpillar is smoky pink and velvety-looking. There is a brownish line along the middle of the back. The spines are “ochreous in colour, tinged with pink, and beset with fine pointed black bristles.” The upper ones are rather stouter than the others, and the pair on the first ring, the only spines on this ring, are rather more than twice the length of the others, and are directed forward over the head, thus giving the appearance of a pair of horns; the second and third rings have each four spines, which are rather finer than those on the rest of the body, which are arranged in six rows. A pale pinkish stripe runs along the lower part of the body; just above the feet. Head black and notched on the crown (Buckler). The chrysalis is brown on the thorax and the body; the wing-cases are more ochreous and marked with black near the edge. There is a black V-mark on the thorax, with a silvery spot on each side, one silvery spot on each side of the head, and other metallic spots on the body near the thorax (Buckler).
On the Continent there are two broods of the butterfly, and specimens are occasionally seen in August in this country; one of these late examples, taken by Mr. Barker in 1881, is shown on the plate (Fig. 6). Sometimes one or two caterpillars of a brood in confinement will feed up and attain the perfect state in August instead of settling down with their companions for hibernation.
The butterfly in June and July frequents similar places to those favoured by the Pearl-bordered, and its distribution in Britain is somewhat similar, although it is a more local species. It seems, however, to be commoner in Scotland than the Pearl-bordered, and has been recorded at least once from Ireland.
Its range abroad extends farther east, as it is found in Corea.