IN THE BRITISH ISLANDS. 49 



fig. 533 (the type) may be described as: ' $ . Anterior wings brown 

 with a purplish or reddish tinge ; median nervure white ; costa whitish 

 with a distinctly pink tinge, but extreme border of costa dark ; stigmata 

 paler but the space between darker. Hind wings whitish-grey." His 

 fig. 534 " is a $ and has the costa whiter and broader than in 533 and 

 no dark edge. There is an ill-developed row of cuneiform spots in 

 both 533 and 534. Hind wings with a dusky lunule and margin" 

 ('Sammlung europaischer Schinet.' &c.). As the Continental vitta 

 appears to be the pale costa form, allied to the non-pale-costa variety 

 known as eruta, it may be advisable to keep the name for this form. 

 The ground colour is normally brownish-red with a slaty tinge, 

 particularly well-developed about the paler areas of the wing as the 

 costal streak, median nervure, &c. 



D. Ground colour greyish-white. 



a. var. pallida, mihi. The ground colour pale greyish- white, with 

 none of the slaty colour characteristic of var. ccerulea ; the abbreviated 

 and complete basal lines edged with fuscous ; the stigmata are repre- 

 sented by clear, very pale spots standing out in the ground colour ; 

 the elbowed line pale ; the extreme hind margin beyond the subtermi- 

 nal line dark grey ; traces of the row of cuneiform spots just inside 

 the subterminal line. Hind wings whitish, darker outer margin. 

 There is sometimes a pale ochreous tinge to be seen in the whiter 

 ground colour, but this represents by far the palest variety of the 

 species we obtain in the British Islands. My specimens have come from 

 Deal and I have not received it from other localities. 



/3. var. sagittifera, Stphs. The following is the description of 

 Stephens' sagittifera : " Head and thorax griseous mixed with white ; 

 anterior wings griseous clouded with white, with a longitudinal, black, 

 arrow-shaped line at the base ; the anterior stigma is rather elongate, 

 ovate, whitish, with the centre pale ashy-brown ; the posterior, griseous 

 in the centre, margined with dusky and white ; the space between, as 

 well as at the base of the anterior stigma, deep fuscous ; the teliform 

 stigma is rather elongate and has a slender black streak extending 

 from it ; on the hinder margin is an angulated pale stripe, having a 

 few dusky wedge-shaped lineolee within ; the margin itself has a row 

 of minute black dots ; on the costa near the apex is a fuscous spot in 

 which are three white dots ; the posterior wings are whitish with the 

 margins dusky ; the $ has the posterior wings milk white." A figure 

 of this variety is given in Humphrey and Westwood's ' British Moths.' 

 There are so many minor differences in the specimens with a whitish- 

 grey ground, that I would include under this name all those specimens 

 whitish-grey in colour, with a pale costal stripe and pale longitudinal 

 central line, with a more or less well-developed fuscous blotch between 

 the reniform and orbicular. 



y. sub-var. olsoleta-pallida, mihi. There is a sub- var. of sagittifera 

 with the same pale greyish-white ground colour, but with the dark 

 fuscous space between the stigmata, characteristic of sagittifera, unde- 

 veloped. The ordinary transverse lines are also practically undeveloped 

 and the variety exhibits a great tendency for the markings to 

 become obsolete. It is in fact (except in colour) a variety almost 

 parallel with sub-var. costa-olsoleta in group A, but has of course no 

 slaty colour. My specimens of this variety have come from Deal. 



