IN THE BRITISH ISLANDS. 9 



dots. The fringe is uniform tile colour. The hind wings are reddish. 

 In the middle is a dark spot and a wavy line. The outer margin 

 rather darker " (< Beitrage zur geschichte ' &c., p. 12). The figure 

 (Plate I., fig. F) to which this description refers, is of a dark red- 

 brown colour. The following note from Mr. W. E. Nicholson, refers 

 probably to this variety : " I had a single specimen of this species 

 from North Wales, which is of a dull brick-red colour. It seems 

 to be a constant form in North Wales " (in lilt.}. I have heard of 

 such dark varieties but have no specimen in my collection. 



Xantliia, Och., Tr. 



This beautiful genus is at once distinguished by its rich colours 

 of yellow, orange, red and purple, and as may be expected, some of its 

 species are very variable. Of the British species, fidcayo (cerayo) and 

 anrayo are by far the most variable, the remainder being compara- 

 tively constant. Cilrago is, as may be readily noticed, not very 

 closely allied to the other species. Perhaps no two species exhibit 

 more than do fnlvago and aurago, the genetic sequence in development 

 of the palest yellow, orange-yellow, red and purplish. Some of the 

 varieties of these two species are very beautiful. Guenee writes : 

 " The imagines of this group generally bear much resemblance to 

 each other. One section (ftdvago (cerago), flavago (silago), aurago and 

 aurantiago) has the superior wings of a beautiful yellow, varying 

 from citron to saffron, with the markings coloured in red. Another 

 section (gilvago, ocellaris and carneago) presents the same designs on a 

 fawn or reddish ground colour. In all, the inferior wings are of a more 

 or less pure white. These species are extremely likely to vary, and 

 it becomes therefore the more necessary to keep a long series, so as 

 not to fall from insufficient data, into the opposite errors (1) the 

 creation of species from varieties, and (2) the reunion of distinct 

 species " (' Noctuelles,' vol. v., p. 391). 



Xantliia, Tr., citrago, Linn. 



This beautiful species is very constant in Britain. The 

 ground colour is of two shades, yellow and orange-red. There is a 

 slight variation in the depth of the central shade. The description 

 by Limueus is as follows : " Noctua spirilinguis cristata, alis deflexis 

 luteis : superioribus fasciis tribus ferrugineis obliquis " (' Sy sterna 

 Naturte/ xth., 518). Taking the palest yellow form as the type, we 

 have an orange form, and Eversmann describes a variety which 

 appears to be very similar to, if not identical with, the type, both 

 forms having the transverse strigte well developed. 



a. var. aurantiago, mihi. The ground colour of the anterior 

 wings of a distinct orange-red colour, instead of the yellow of the 

 type ; otherwise marked like the type. My reddest forms have come 

 from Cannock Chase and Heading. 



(3. var. subflava, Ev. This is described by Stauclinger as: " Al. 

 ant. fascia basali limboque Jato infuse." (' Catalog,' p. 117) and is given 

 as coming from the " Ural and Petropolis." 



Xanthia, Tr.,fukago, Linn, (cerago, Fab.). 



This is a most beautiful species and the most variable in the 

 genus. The ground colour extends from a pale lemon-yellow, often 



