IN THE BRITISH ISLANDS. 47 



!l.-With ill- developed transverse markings 

 = var. nigro-fusca, Esp. 

 O TIT*J.T- 3' J.' L 1 



2.-With distinct markings = var. gypcetma, 

 Gn. 



L. Ground colour black. 



a. Without pale costa. With more or less distinct markings = var. 



nigra. 



( l.-With the costal streak ill-developed = var. 



b. With pale costa.... } 9 ?.?? B *? a ' St ; , 



I 2. -With the costal streak well-developed var. 



( costa-nigra. 



A. Ground colour pale slaty-grey. 



a. var. obsoleta, mihi. This very rare variety is of a pale grey 

 colour, lightly dusted with slaty scales, there are no distinct markings, 

 but there is the faintest possible trace of a basal line, and the orbicular 

 and reniform are represented by being slightly paler than the ground 

 colour. There is also a faint trace of the subterminal line. Hind 

 wings pure white in the type, but those of both sexes vary slightly 

 from pure white to white with the outer margin grey. Sub- var. puncta- 

 obsoleta. Like the above but with a faint ochreous tint, and the lower 

 part of reniform filled in as a small black dot. Hind wings of the male 

 pure white, of the female, white with a dark grey outer margin and 

 dark grey lunule. Both these forms are very rare, I have seen them 

 from Deal only. 



ft. var. costa-obsoleta, mihi. Of the same pale slaty-grey ground 

 colour as in var. obsoleta, but with the costa dusted with still paler 

 grey and the three stigmata outlined in paler, so that this form, although 

 of the same obsolete character, has a distinct costal streak. There are 

 indications of the cuneiform spots. The form is apparently very rare. 

 I have it from Deal only. 



y. var. nana, Zell. In the British Museum is a very small sub- 

 var. of costa-obsoleta with Zeller's label. It is a $ , with a costal streak 

 developed, and paler stigmata ; traces of a row of cuneiform spots. 

 Hind wings grey with paler base ; expanse not more than f of an inch. 

 I have an almost identical specimen from Deal, but it must be rare, as 

 I have no other specimen. I do not know whether this variety has 

 been described or whether it is simply a M.S. name found in Zeller's 

 collection. 



B. Ground colour clear slate or dove-colour, 

 a. var. ccerulea, mihi. The ground colour of the anterior wings of 

 a pale slate or dove-colour, which shows up most clearly on the inner 

 margin, the median nervure, the costal area and between the (more or 

 less) ill-developed cuneiform spots. The transverse lines edged with 

 fuscous, the orbicular round and generally white (sometimes of the 

 ground colour), the reniform also pale ; the longitudinal area in which 

 the reniform and orbicular are placed, slightly suffused with fuscous, 

 and fuscous dots on the costa show the commencement of the transverse 

 lines; the cuneiform spots blackish-fuscous. Hind wings greyish- 

 white with dark outer margin. I have only seen this beautiful variety 

 from Deal, and have no knowledge of its occurrence in other British 

 localities. In its extreme form, this is the finest variety of the species 

 I have ever^seen. 



