110 VARIETIES OF NOCTUJB 



with red or purplish = sigma, Haw. ; the last, pale grey, with no trace 

 of red = sigma, Hb. The sigma of Haworth is the commonest form, 

 and appears to be the most widely distributed. There is a great deal of 

 variation in the quadrate spots before and beyond the orbicular. Generally 

 they are separate, but often they are united, with every gradation ; the 

 most opposite forms having two distinct quadrate spots when quite 

 separate, and a distinct arch when they are completely joined. There 

 is some variation in the depth of colouring and intensity of development 

 in the transverse lines, sometimes the latter are quite obsolete. There 

 is also occasionally a trace of a transverse shade and a little mottling 

 under the stigmata. Guenee describes a var. A, of which he writes : 

 " The black space which separates the two stigmata, narrower, more 

 concave at the extremities, without black spots at the abbreviated basal 

 line." " From the State of New York " (' Noctuelles,' vol. v., p. 330). 



a. var. intermedia, mihi. sigma, Haw. The sigma of Haworth is 

 intermediate between the red type and the pale sigma of Hiibner. 

 His diagnosis is : " Noctna alis griseo-purpurascentibus atro maculatis ; 

 stigmatum marginibus strigisque quatuor pallidis nigro adnatis." 

 " Abdomen fuscum, ani barba rufa. Alae anticse strigis quatuor ordi- 

 nariis pallidis obsoletis ; viz. duabus ante, duabusque aliis pone stigmata 

 margine subluteo nigro adnato conspicua. Macula atra ante, alteraque 

 inter stigmata ut in ultima : macula alia parva basi, et quatuor vel 

 quinque costales, una parum major juxta apicem, exacte ut in N. baja, 

 quae ad strigam quartam adtingat " (' Lepidoptera Britannica,' p. 225). 



/3. var. sigma, Hb. This is the palest form of the species. 

 Hiibner's form is pale grey in colour, with the markings around the 

 stigmata very black. The costal spots are geminated, the median 

 nervure pale with a slight red shade just under the stigmata, below 

 the median nervure " (' Sammlung europ. Schmet.,' fig. 497). This is the 

 var. ft of Haworth's sigma, which he describes as : " Alis albidis vel 

 albicantibus, character ibus fere ut in a (= sigma, Haw.) " (' Lep. Brit.,' 

 p. 225). 



Noctua, Linn., c-nigrum, Linn. 



The Linnaaan description of this common species is as follows : 

 " Noctna spirilinguis cristata, alis depressis cinereis : macula nigra ex- 

 tus obsoleta lineolaque apicis atra." " Lineola nigra ante apicem ad 

 marginem exteriorem " (' Systema Naturse,' x., p. 516). To which is 

 added in the 'Fauna Suecicas,' pp. 316-317: " Alae superiores supra 

 cinereae, macula laterali atra, oblonga, arcuata in sinu lutea ; macula reni- 

 formis flavescens ; litura nigra versus marginem posticum. Alaa 

 inferiores supra fere niveae. Alae omnes subtus cinerascentes arcu 

 magno obsolete fusco, literam C mentiente. Thorax antice griseus." 

 This species has the C-like mark round the orbicular very complete, 

 although variable in minor particulars of shape. I have no specimen 

 in which the two quadrate spots are distinct. 



a. var. nunatrum, Esp. Of this variety Guende writes : " Paler, 

 the ordinary lines obliterated, a row of interrupted black dots, terminal 

 space very black." He also adds : " This variety, which is generally 

 accidental, must not be confounded with the N. nunatrum of the ' Wien. 

 Verz.,' which is the gothica of Linnaeus " (' Noctuelles,' vol. v., p. 328). 

 Esper writes : " The authors of the 'System. Verz.' have not noted 

 Ph. gothica by the Linnaean name, but they mention it by the name 

 nunatrum, under which name I have received it from those parts. The 



