Lepidoptera The Holly Blue Butterfly – Lycana Argiolus
While all the other Blues delight to sport on low flowery banks in the full blaze of the summer’s sun, the Holly Blue prefers to flit among the branches of trees, often many feet from the ground. The larva feeds on the flowers of the holly (Ilex Aquifolium) in the spring, and on those of the ivy (Hedera Helix) late in the summer; also on the alder buckthorn (Rhamnus Frangula); and it is in localities where these grow that we may find this lovely Blue sporting among the branches, or resting on a leaf with its wings folded together, thus making itself conspicuous among the dark foliage by exposing the pale silvery blue of its under surface.
Fig. 92.-The Holly Blue-Under Side.
The upper sides of both the male and female are shown on 
Plate VII (figs. 3 and 4 respectively), where the beautiful lilac blue will be seen to have a border of black, wider in the latter than in the former.
The under surface is spotted with black, as shown in fig. 92, and has no border of orange spots.
This is a double-brooded butterfly, appearing first in April and May, and then again in August. It is not at all uncommon in the south of England, and extends northward as far as the Lake District, but is not found in Scotland. It is generally distributed throughout Ireland.
The caterpillar may be looked for in June and October. It is light green, with a line of dark green down the back.