The species is double brooded on the Continent, and occasionally a few butterflies will appear in August, but such emergences depend on a combination of favourable circumstances. In very forward seasons it has been seen on the wing during the last week in April.
Its range extends over Europe and into Northern Asia.
As Barrett refers to the capture in Norfolk (May or June, 1860) of several specimens of the Central and South European species, H. alveus, Hüb., it maybe well to mention it here, if only for the purpose of quoting his remarks thereon. After detailing the facts connected with the occurrence, he states, "It seems undesirable now to introduce the species to a place in the British list, but rather to record the captures in question as specimens accidentally introduced with plants, or else the result of a very exceptional act of migration."
The Dingy Skipper (Thanaos tages).
The wings are fuscous, with darker fuscous transverse bands on the middle third of the fore wings; the space between these is sometimes, and in both sexes, whitish; there are some whitish spots on the outer band, usually towards the costa, but occasionally on the middle also, and a series of white points on the outer margin of all the wings. The hind wings have a whitish discal dot and a band beyond the middle, which is almost parallel with the outer margin. The male has a well-marked fold on the costa (Plate [122]).
The egg is whitish-green when freshly laid; it afterwards changes in colour to orange. The caterpillar is yellowish-green with a darker line along the back and a paler line on each side; the spiracles are red and edged with whitish. The head is pale brown, striped and marked with purplish-black. The body, together with the head, is covered with a short whitish pile. It feeds on bird's-foot trefoil (Lotus corniculatus) from June until August, when it hibernates. I have not seen the chrysalis, but it has been described as dark green with the body tinged with rosy red.
The butterfly is on the wing in May and June; in some seasons it has been seen as early as the end of April. Very occasionally, perhaps, there is a partial second flight in August. It has been reported as plentiful at Lyme Regis in August.
I took one or two specimens about the middle of August, 1903, in the New Forest district, and in the same month of 1905 one of two caterpillars sent to me by Dr. Chapman pupated in August, and the butterfly emerged some time in the autumn, as I found it dead in the box early in October. Both the caterpillars had spun together sprays of the food-plant as shown in the figure, Plate [123]. One was removed for its portrait to be taken, and it was supposed that the other bundle contained a caterpillar also, and was not examined.
