12 VARIETIES OF NOCTILS! 



Xanth/a, Tr., flavago, Fab. (silago Hb.). 



This is a most constant species, considering the amount of variation 

 in its two nearest allies (fulvago and aurago). The ground colour pre- 

 sents practically no variation. The red markings in the centre of the 

 wing, consist sometimes of a number of red dots, at others, of a 

 distinctly solid red band. The normal red parts of the wing vary 

 from bright red to dark purplish. The type is thus described by 

 Fabricius : "Noctua cristata, alis deflexis flavissimis : punctis fasciaque 

 lata fuscis." " Ala3 anticas flavissimae punctis aliquot fuscis. Macula 

 niagna baseos ad rnarginem exteriorem fusca. Pone medium fascia 

 lata, sinuata, fusca, in qua puncta tria costalia, flava. Pone hanc striga 

 e punctis parvis fuscis. Ala? posticee cinereas " (' Mantissa,' p. 160). 

 Guenee writes of this species : " A little less common than cerago. 

 One readily distinguishes the varieties of these species, even when most 

 nearly alike, by the colour of the head and collar, which are in silago 

 of a ferruginous-brown " (' Noctuelles,' vol. v., p. 394). The following 

 are the only vars. of the species described : 



1. With the central band complete and dark in colour = flavago , 



Fab. 



2. With the central band complete, red = var. ochreago, Bork. 

 3. -With the central band broken up, red = var. togata, Esp. 



a. var. ochreago, Bork. This differs from the type only in having 

 a complete red central band instead of a dark purplish-fuscous band. 

 Borkhausen writes : " The ground colour of the fore wings has reddish 

 markings. These consist of a spot near the outer margin, a central 

 band and another spot near the base (on the costa). The central 

 markings are red (rosy), extending into a band reaching from the costa 

 to the inner margin " (' Naturgeschichte ' &c., p. 671, No. 288). This 

 would appear to be the silago of Hiibner. 



f3. var. togata, Esp. This is the form in which the central band 

 is broken into transverse series of dots, more or less complete. Esper's 

 description is : " Noctua spirilinguis cristata, alis deflexis flavis, disco 

 saturatiore, serie triplici macularum unaque punctoruin margmalium 

 rubescentium, inferioribus pallidis " (' Die Schmet. in Abbildungen ' 

 &c., p. 336). 



Xanthia, Tr., aurago, Fab. 



This is another most beautiful and most variable species. I am 

 indebted entirely to the Reading collectors, especially to Mr. Holland, 

 for my specimens and for notes on the species. The ground colour 

 varies from the palest yellow, to deep purplish-red, through orange. 

 The orange-red and purplish-red have both almost unicolorous forms, 

 but the pale yellow is, so far as I know the species, always banded. 

 Mr. Holland writes.: "Aurago, here Eeading varies beautifully 

 but gradually from the pale yellow which is the commonest form 

 through orange to one uniform purplish colour. From a long series 

 you might pick out at least five vars., looking distinct enough 

 represented poorly, but as well as I can now, by the four top specimens 

 I am sending you, and the extreme purple var. just mentioned " (in 

 litt. Oct.' 91). Strange to say, I had already divided the specimens I 

 had by me as Mr. Holland suggested. This was as follows : 



