IN THE BRITISH ISLANDS. 17 



ft. var. unicolor, Stdgr. Staudinger gave this name to the form 

 described by Guenee as var. A. His description is : " The whole of 

 the wing of a clear carnation-red, with the before mentioned parts 

 (sides of median space and outer margin) and often the median space 

 much darker, the latter then absorbing the reniform stigma ; the two 

 median lines generally more distinct, and marked in pale yellow. The 

 two sexes similar " (' Noctuelles,' vol. v., p. 402), whilst Staudinger's 

 description is : " Al. ant. fere unicolor. rufescentibus, flavo-bistri- 

 gatis " (' Catalog,' p. 1 16). In Britain, this variety is generally known as 

 the Manx form, but it is recorded from Ripon (' Young Nat.,' viii., 

 p. 223), and I have seen specimens from Derbyshire and Gloucester- 

 shire, whilst the Rev. G. A. Small wood has given me a specimen captured 

 in his locality (Burton-on-Trent). Of the Manx form, Mr. Birchall 

 writes : " I have received a fine series of Cirrcedia xerampelina, 

 captured in the Isle of Man during the present month, by Mr. 

 Warrington of Douglas. The specimens are all very richly coloured, 

 and some of them present a remarkable variation from ordinary 

 English examples, the golden-yellow of the fore wings being replaced 

 by reddish-brown ; two narrow lines of yellow only remain bordering 

 the median band, the inner margin of which is not indented near the 

 costa, but runs in a straight and uninterrupted line across the wing. 

 In general aspect, the moth is more like Leucania conigera than 

 xerampelina. Mr. Doubleday informs me that these specimens are 

 identical with the form of xerampelina found in Central France, and 

 that he is not aware that the variety has been previously taken in the 

 British Islands. The appearance of the same variety, and that a very 

 striking one, in localities so widely separated by distance and climatal 

 conditions as Central France and the Isle of Man, is somewhat 

 startling, and shows how little we really know of the causes 

 governing the production of varieties and their preservation or 

 extinction in different portions of what we may suppose was once a 

 continuous territory. In the South of France, Mr. Doubleday 

 informs me, xerampelina assumes another form being very small and 

 dull-coloured " (' Entom.,' iv., p. 324). Unicolor is the var. obscura of 

 Cockerell (' Entom.,' xxii., p. 55). 



6. Family : Cosmidce, Gn. 



This family, although closely allied to the preceding, has no 

 very decided connection with the following (Hadenidce), the affinities 

 of which are decidedly with the Apamidce. Some of the species 

 included in the Cosmidce have a superficial resemblance to certain 

 genera in the Orthosidce. We find in none of the species, with the 

 exception of Calymnia trapezina, the extreme variation presented by 

 certain species in the Apamidce, Noctuidce or Orthosidce. In trapezina 

 the variation is extreme, but otherwise, the members of this restricted 

 family are, at any rate so far as we know them in Britain, remarkably 

 constant, Dicycla oo perhaps showing more variation than the remain- 

 ing species. As tree-frequenting species, " natural selection " has but 

 little play in producing melanism or any of the forms of variation 

 common in other families. 



Dicycla, Gn., oo, Linn. 



This pretty species varies in ground colour from a pale yellowish- 



