QUADRIFIDjE. 261 



Variable in the depth of ground colour of the fore wings 

 as already indicated, still more so in the depth and extent of 

 dark clouding, which in some examples is hardly existent, in 

 others is so deep and extended that the white about the 

 stigma is obliterated ; while in other specimens, otherwise 

 extremely, dark this shows up clearly and conspicuously. 

 One of the most beautiful forms is strongly tinged with soft 

 yellow-brown, and has oval spots of orange-ochreous between 

 the second and subterminal lines. Sometimes, in the female 

 especially, the basal and dorsal region of the hind wings is 

 tinged with black. In the collection of Mr. S. J. Capper is 

 a specimen having the black band of the hind wings of 

 nearly double its usual width. 



On the wing in July and August. 



Larva elongated, attenuated at each extremity ; ninth 

 segment swollen and humped ; twelfth segment humped and 

 with two dorsal prominences ; all the dorsal spots raised into 

 little red warts emitting black bristles; undersurface much 

 flattened ; a fringe of fleshy filaments extends along the 

 sides above the legs and prolegs, which sprawl outwards ; 

 head hardly bifid, pale brown ; face flattened and outlined 

 with black ; general colour greyish-brown with a greenish 

 tinge and dusted with black; the fifth segment, and the 

 incisions between the eighth and ninth and the tenth and 

 eleventh, paler, the hump on the ninth tipped with ochreous ; 

 spiracles edged with black ; undersurface greenish cream- 

 colour, with four conspicuous purplish-brown spots between 

 the prolegs ; legs tinged with pink. (C. Fenn.) 



April to June on oak; when very young preferring the 

 blossoms (catkins), but soon commencing to feed on the 

 leaves, to which it then devotes itself. 



Pupa elongate, rounded, tapering considerably to the anal 

 extremity, which is hooked. Reddish-purple — the colour of 

 an Orleans plum — covered with a bluish efflorescence. In a 

 rather strong but loosely-made cocoon of wiry whitish silk 



