Richard South

“ The female is white in colour, and usually only lightly speckled with blackish; the cross lines are more conspicuous, as a rule, than in the male, but they are subject to pretty much the same kind of aberration. Sometimes examples of this sex greatly resemble Fidonia carbonaria, and have been confused with that species by Haworth and other entomologists in the past. An abnormal specimen with six wings has been recorded, and Barrett mentions a gynandrous example—the right side like a small dark female, and the left an ordinary male ”

“ The hind wings have two cross lines corresponding with the first and third on the fore wings. There is a good deal of variation in the amount of dark speckling, and this is occasionally so heavy that the insect becomes dark grey in colour; I have taken such specimens at Oxshott in Surrey. Dark aberrations are perhaps more frequent in the north of England, but the species is more local and less plentiful in that part of the country.
The caterpillar, which may be beaten from birch, and sometimes alder, in July, is bright apple green with yellowish lines on the sides and back ”

“ There is variation in the ground colour of the male, from white to greyish, and the markings are sometimes greyish brown and sometimes blackish. Kane states that, in Ireland, a large number of Connemara specimens have the fore wings entirely white, broken by dark veins, front margin, and three streaks parallel to the outer margin. The caterpillar is greenish, with dusky grey lines and freckles on the back, and a yellow stripe low down along the sides ”

“ Female moths taken at light may not always be in first-rate condition, but they will probably lay eggs, and should be kept for that purpose in a chip box. The caterpillars do not hatch out until the following spring. Put the eggs in a cool place.
Early Thorn (Selenia bilunaria) .
The sexes of the spring or typical form are depicted on Plate 112, Figs. 1 ♂, 2 ♀, and the paler summer form var. juliaria (July Thorn) , Haworth, is represented by Fig. 3. The underside is shown in Mr. H. Main's photo of the moth in its natural resting attitude. ”

“ The caterpillar is reddish brown, with a black-edged dark-green irregular line along the middle of the back; a white line on each side of the central one, and following this are a dark-brown shade-like stripe and some brownish-green lines; the line along the spiracles is whitish, inclining to yellow. ”

“ Dark brown or blackish specimens (ab. unicolorata, Staudinger) are captured now and then in the southern counties of England, but such uniform dark varieties are more frequent in the north (Staffordshire and Yorkshire) . ”

“ Note.—Cross-pairings between bistortata ♂ and crepuscularia ♀ resulted in the ab. ridingi, Tutt, whilst the offspring of a crossing of crepuscularia ♂ and bistortata ♀ have been named bacoti, Tutt. Pairings of bistortata ♂ and delamerensis ♀ produce ab. ridingi-suffusa, Tutt; and those of delamerensis ♂ and bistortata ♀ = bacoti-suffusa, Tutt. ”