312 LEPIDOPTERA. 



Underside of the fore wings whitish-yellow, tinged along 

 the costa and hind margin with pnrplish-red and with two 

 orange-red dashes from the costa before the apex. Hind 

 wings white. Body and legs yellowish-white. 



Usually but little variable, though in some individuals the 

 markings are more sharply defined and richly coloured than 

 in others. Occasionally the yellowish-white ground is faintly 

 obscured by a slight shading of purple-red from the lines. 

 But there is a very handsome recurrent form, known as var. 

 muxgo, in which the whole broad area of the fore wings from 

 the outside edge of the reniforra stigma to the subterminal 

 line is filled with rich purple-red, forming a wide band across 

 the wing, and continued along the dorsal area till it joins the 

 basal blotch ; in this form the portion of this broad band 

 which lies between the second and subterminal lines is 

 frosted with plum-colour as in the basal blotch. Such 

 examples appear to be more frequently founel in Northamp- 

 tonshire than elsewhere. There is besides a little tendency 

 to local variation in colour, those taken in the New Forest, 

 Hants, being of a more yellow tint than those from Essex ; 

 and in some individuals the two upper stigmata are joined at 

 their margins. 



On the wing at the end of June or beginning of July, 

 all emei'ging almost in one day, and continuing out but a 

 very short time. 



Larva cylindrical, the head only a little less than the 

 second segment, full and rounded, jet black and glossy ; 

 general colour of the body jet black, except the anal flap 

 and the undersurface, which are dark brown ; dorsal plate 

 as glossy as the head ; the rest of the skin having but a very 

 slight gloss ; dorsal stripe pure white, narrow on the dorsal 

 plate and thoracic segments, broader on the rest, but on each 

 contracted in the middle and divided so as to form a series of 

 long elliptical marks ; from two isolated spots on the side of 

 the dorsal plate arise the subdorsal lines, pure white, com- 



