Lepidoptera The Large Blue Butterfly – Lycana Arion
The last of our Blues is the largest of the genus, and is, with the exception of Semiargus, the rarest. It is a very local insect, appearing in small numbers, during June and July, in parts of South Devon, Gloucestershire, Northamptonshire, and a few other counties.
The colour of the upper side is a dark and rich blue, with a broad dark border on the hind margins, and a group of black spots near the centre of the fore wings. The under side (fig. 95) is of a pearly grey, without any red spots, but having a double border of black spots, and also an irregular row of black spots in white rings across the middle of each wing.
The caterpillar feeds on thyme (Thymus Serpyllum), on which plant the eggs are laid singly, generally on the flower heads.