THE BLACK HAIR-STREAK. (Thecla Pruni.)
([Plate XII]. fig. 2.)
The upper side is very dark brown, sometimes almost black, and bearing near the hinder edge of the hind wings a few orange spots. This character will at once distinguish this from the next species (W. Album). On the under side of the hind wing is a broad band of orange, having a row of black spots on its inner edge.
The caterpillar is green, with four rows of yellow spots. It feeds on the sloe.
The butterfly comes out about the end of June or in July. It is generally a very rare insect, but is occasionally taken in great plenty in certain spots. The Rev. W. Bree, writing to the Zoologist from the neighbourhood of Polebrook, North Hants, says, "Thecla Pruni is very uncertain in its appearance. In 1837 it literally swarmed in Barnwell and Ashton Wolds; I do not scruple to say that it would have been possible
to capture some hundreds of them, had one been so disposed; for the last few years it has appeared very sparingly indeed." It has also been found in the following localities:—Overton Wood; Brington, Huntingdonshire; and Monks Wood, Cambridgeshire.
THE WHITE LETTER HAIR-STREAK. (Thecla W. Album.)
([Plate XII]. fig. 3.)