Lepidoptera The Common Blue Butterfly – Lycana Icarus
Although this pretty little butterfly is so common that it is almost sure to be known to all who take any interest in insect life, yet it is important to observe it carefully, since it is an easy matter to confound it with other species of the same genus.
The upper surfaces of the two sexes are very different, that of the male (Plate VI, fig. 15) being a beautiful lilac blue; and that of the female (Plate VI, fig. 16) a dark brown, powdered with blue at the bases of the wings, and having generally a border of orange spots, more or less defined, on the hind margins of all wings.
The under side, shown in the accompanying woodcut, is ashy brown; warm in the female, but paler in the male. The hind wings, and sometimes all four, are bordered with orange spots; and this species may be distinguished from Astrarche by the presence of two black spots, in white rings, near the base of the fore wings.
There will be no need to name localities for this insect, as it is abundant everywhere, frequenting meadows, heaths, and all waste places. It is double brooded, and is on the wing continuously from May to September, the first brood enduring from May to July, and the second from July to the end of the warm weather.
The caterpillar is green, with a dorsal line of a darker tint, and a row of white spots on each side. It feeds on clover (Trifolium pratense and T. repens), bird’s-foot (Ornithopus perpusillus), bird’s-foot trefoil (Lotus corniculatus), and the rest-harrow (Ononis spinosa).
The chrysalis is short and rounded, of a dull green colour, tinged with brown on the under surface.