NOTODONTID^. 163 



cloud at the anal angle, and a faint indication of a yellowish 

 blotch at the base of the dorsal margin ; hind margin edged 

 with a thick black line, broken at the tip of each nervure, 

 and often forming slight scallops, or Itmules; cilia yellow, 

 edged with bright red-brown and toothed by purple-brown 

 projections at the nervure-tips. Hind wings rather ample, 

 much rounded, furnished with very long silky scales at the 

 base; pale yellow, usually with faint indications of two 

 parallel greyish cloudy stripes half-way across the wings from 

 above the anal angle ; but in some specimens these are 

 hardly perceptible, in others extended further across the 

 middle of the wing and broadened into a smoky cloud ; cilia 

 yellow, faintly dotted with chocolate-red. Female larger and 

 stouter, with the antennae stout, and furnished with pairs 

 of bristles in rows, otherwise similar. 



- Underside of all the wings creamy yellowish-white, each 

 with an undulating transverse narrow chocolate stripe, 

 crossing the middle of the hind wings, bent beyond the 

 middle and oblique in the fore wings ; hind margin of the 

 fore wings edged and rippled with chocolate, and having 

 similar lines and spots in the yellow cilia ; body pale yellow ; 

 legs purple-brown barred with yellow, and furnished with 

 large tufts of scales, purple in front, yellow behind. 



Variation in this species is usually in the degree and 

 extent of the silvery-white shining scales over the fore wings 

 and the degree of rippling over the darker under-colour. In 

 some specimens this is almost confined to the base, in others 

 it extends to all the dark portions of the wings, and every 

 possible intermediate degree occurs; but the most extensively 

 and beautifully rippled specimens seem to be obtained in 

 Lancashire. In the collection of Mr. W. G. Blatch is a female 

 specimen, reared in Warwickshire, in which the silvery-white 

 colour is intensified to shining snowy-white, which extends 

 over a large portion of the fore wings ; while the first and 

 second lines, in striking contrast, are strongly marked and 

 of a rich red-brown. In Yorkshire a very different form is 



