THE SILVER-WASHED FRITILLARY (Argynnis Paphia.)
([Plate IX]. fig. 4, Male; 4 a, Female.)
The beautiful genus to which this butterfly belongs is distinguished by the adornment of silvery spots and streaks with which the under side of the hind wings is bedight; while the upper surface is chequered with black, upon a rich golden-brown ground, the device reminding one of those old-fashioned chequered flowers called "fritillaries," whence the common name of these butterflies.
Of all the British Fritillaries, this is, perhaps, the loveliest, from the exquisite softness and harmony of the silvery pencillings on the iridescent green of the under side; though some of the others with bright silver spots are gayer and more sparkling.
The two sexes differ considerably on the upper surface; the male being marked with black (as in the engraving) upon a bright orange-brown ground, while the female is without the broad black borders to the veins of the front wings, and the ground colour is suffused with an olive-brown tint, inclining sometimes to green. The black spots are also larger. Beneath, however, both sexes are marked nearly alike with washy streaks of silver, and not with defined spots.
The caterpillar (fig. 7, [Plate I].), as with all the Fritillaries, is thorny, with two spines behind the head longer than the rest; black, with yellow lines along the back and sides. It feeds on violet leaves, also on the wild raspberry and nettle.
The chrysalis (fig. 16, [Plate I].) is greyish, with the tubercles silvered or gilt.
The butterfly is out in July and August, and is not rare in the woods of the South and Midland districts, but it also extends its range into Scotland. On the banks of Wye, about Tintern and Monmouth, I found it extremely abundant. It has been seen swarming in a teasel-field, near Selby, Yorkshire.