SERICORID.-E—P^DISCA . 135 



without the costal fold, in other respects resembling the male 

 in every phase of variation. 



Underside of the fore wings glossy leaden brown ; costa 

 and hind margin shaded with the ground colour of the upper 

 side. Hind wings pale leaden brown. 



Always and everywhere variable, not only as already sug- 

 gested, but also on quite different lines. One range of forms 

 always found along with typical specimens has a dorsal blotch 

 extending along almost the whole dorsal margin and doubly 

 humped ; in this form the dorsal blotch is nearly always red- 

 brown and usually darker than the ground colour — which in 

 this case is sometimes nearly white. Another form, found 

 freely in Scottish mountain districts, has the ground colour 

 usually of a bright light red or terra-cotta colour, with the 

 markings sharply defined and either broken or added to, or 

 even changed to elongated dashes producing varieties which 

 are extremely pretty but tedious to describe. 



On the wing from the end of June till August. 



Larva sluggish, flattened yet swollen in the middle ; dull 

 white, tinged faintly on the back with bluish grey, which is 

 interrupted at each segmental division ; head pale brown, 

 with the jaws dark brown ; dorsal and anal plates whitish. 



When younger, more greenish grey with the raised dots 

 black and the hairs rather long ; head and dorsal plate black ; 

 the anal plate dull green ; feet black. 



May and June on sallow, birch, hazel, aspen, dogwood and 

 alder ; drawing together the leaves and 3'oung shoots and 

 feeding within. 



Pupa yellow-brown ; in a cocoon in the earth. 



This species is particularly noticeable at harvest time when 

 the great glut of summer species is over. It hides during the 

 day in bushes and hedges, and rushes out with great vigour 

 when disturbed by the beating stick, to fly often, to a consider- 



