THE SATIN WAVE. II7 



and Norfolk (Thetford). Possibly there are other localities 

 in England, more especially in the west, where this species 

 may be awaiting discovery. 



The Satin Wave (Acidalia {Ptychopoda)^stibsertceata\ 



The wings of this species (Plate 45, Fig. 17) are glossy 

 whitish, with a faint greyish, or sometimes yellow greyish, 

 tinge ; the cross lines are grey, oblique and straight on the 

 fore wings, but the outer two on the hind wings are curved 

 or bent. 



Var. mancimiata^ Knaggs, a local form found in Lancashire 

 and Yorkshire, is rather more tinged with yellowish, the lines 

 being distinct, and some more or less distinct dusky dots on 

 the outer margin of the fore wings. 



A blackish form, with white fringes, has been recorded from 

 North Cornwall, where the species, in its usual form, has been 

 noted as abundant. 



The rough-looking caterpillar is pale greyish, inclining to 

 reddish above ; three black lines along the back, the central 

 one slender, and the outer ones widening out towards each end. 

 It feeds on knotgrass, dandelion, chickweed, and other kinds of 

 weeds, and will eat plum. Hatching in August, it hibernates, 

 as a rule, and attains full growth in the following spring ; but 

 sometimes caterpillars feed up quickly, and produce moths the 

 same year. 



The moth, which is out in June and July, is partial to heathy 

 ground, but not confined to heaths, as it has been met with in 

 lanes bordered by pasture fields. Widely distributed through- 

 out England and Wales, rare in Scotland, where it has only 

 been recorded from the Sol way. In Ireland it has been found 

 commonly at Howth, near Dublin ; and in the counties Cork 

 and Waterford. 



