IN THE BRITISH ISLANDS. 19 



part of the wing area of the darker coloration, and reducing the pale 

 ground colour to the central area and the extreme outer margin. 

 Haworth's diagnosis ia:" Noctua alis fusco ferrugineoque variis, 

 stigmatibus. tribus, basi et medio costa^, fasciaque marginal! flavis." 

 " Sequenti (f&rvugmago) simillima, at vix eadem, alis longe saturatiori- 

 bus. Flavedo costas secta est lineola ferruginea basi, tribusque aliis 

 in medio. Fascia marginalis composita est ex maculis regularibus 

 confertis, at distinctis. Stigma anticum rotundum, posticum cordiforme, 

 tertium lineola crassa est. Ala3 postica3 albtB " (< Lepidoptera 

 Britannica,' p. 238). Of this variety Staudinger writes : " Al. ant. 

 fuscis, macul. margineque exteriore flavis " (' Catalog,' p. 114). 

 Cosmia, Och., paleacea, Esp. 



This species has much of the superficial appearance of Xanthia. 

 It varies but very little. There is a difference in the tint of ground 

 colour, which varies from pale yellow almost to orange, and the trans- 

 verse lines are better developed in some specimens than in others. The 

 lower part of the reniform generally stands out conspicuously as a dark 

 fuscous spot, otherwise there is but little variation. Esper's diagnosis 

 of the type is : " Phalcena. Noct. spirilinguis subcristata, alis flaves- 

 centibus, stria una alterave rufa, stigmatibus ordinariis pallidioribus, 

 reniformi macula fusca foeta." The figures to which this description 

 refers may be described as : " $ . Pale yellow ground colour, distinct 

 reddish transverse lines and outlines to stigmata, lower part of reniform 

 blackish. 5 . Bright orange, no basal line, orbicular indistinct, 

 lower part of reniform filled in with blackish, elbowed line reddish " 

 ('Die Schmet. in Abbildungen ' &c., p. 323; pi. 122, figs. 3, 4). 

 Guenee describes two forms, the pale yellow or typical form and a 

 darker orange-yellow form, the latter of which is the angulago of 

 Haworth. The fulvago of Hiibner is identical with Esper's type. 



a. var. angulago, Haw. This richer coloured variety is not only 

 the angulago of Haworth, but also the var. A of Guenee, who 

 writes :- " Anterior wings of a beautiful rich orange-yellow, with the 

 markings of a dark ferruginous. The female is speckled, in places, 

 with rosy-ferruginous, which destroys the contour of the stigmata " 

 (' Noctuelles,' vol. vi., p. 7). Haworth's diagnosis is : " Noctua alis 

 aureis, striga unangulata ante, alteraque pone stigmata ordinaria 

 subferrugineis " (' Lepidoptera Britannica,' p. 239). This form seems 

 almost as common in Britain as the type. 



Plastenis, Bois. (Tethea, Och.), retusa, Linn. 



This is another species that varies little. Besides the typical 

 olive-grey specimens, reddish examples occur. I have noticed no 

 other form of variation worthy of mention. The type of this species 

 is thus described : " Ph. Noct. retusa spirilinguis subcristata, alis griseis 

 retusis : strigis tribus pallidioribus." " Alas superiores posticae retusa>, 

 colore cinereo-grisescente, minime nebulosas, strigis tribus pallidioribus : 

 prima ad basin ; secunda oblique transversalis, quam macula ovalis et 

 reniformis excipit ; tertia transversalis obliqua, quam linea transver- 

 salis flexuosa sequitur. Subtus ala3 cinerea3 puncto et arcu fuscis " 

 (' Fauna SuecicaB,' pp. 321-322J. The reddish tinted specimens men- 

 tioned above form the grdcilis of Haworth. 



a. var. gracilis, Haw. Haworth himself when describing retusa 



