IN THE BRITISH ISLANDS. 13 C J 



sallow. Here, at any rate, is a natural experiment which shows that 

 heredity beats temperature out of all calculation. If Mr. Merrifield's 

 experiments be correct, my instabilis should be certainly darker than 

 usual, or, at any rate, some part of the brood should be darker, but the 

 reverse is the case. This is an extreme case in point of temperature, 

 for none of Mr. Merrifield's pupae were ever frozen for six weeks, at 

 least, as far as I recollect ('Entom. Record ' &c., vol. ii., p. 55). 



The following is a general classification of the chief varieties of 

 this species : 



1. Pale whitish-grey, with central band = instabilis, Fab. 

 la. Pale whitish-grey, without central band = var. pallida, Lampa. 

 2. Pale slaty or bluish-grey, with central band = var. ccerulescens. 

 3. Dark slaty-grey, with reddish tint and central band = var. 



nebulosus, Haw. 



3a. Dark slaty-grey, almost unicolorous = var. subsetaceus, Haw. 

 4. Pale brownish or reddish-grey, with central band == var. trigutta, 



Esp. 



4a. Pale brownish or reddish-grey, unicolorous = var. rufo-grisea. 

 5. Dark brownish-grey, with central band = var. virgata-brunnea. 

 5a. Dark brownish-grey, unicolorous = var. unicolor-brunnea. 

 6. Dark shiny red-brown, with central band still darker = var. 



instabilis, Hb. 



6a. Dark red-brown, unicolorous = var. instabilis, Esp. 

 6b. Dull red-brown = var. contacta, Esp. 

 7. Reddish-black, unicolorous var. angustus, Haw. 

 8. Shiny black, unicolorous = var. fuscatus, Haw. 

 9. Dull sooty-black, unicolorous = var. atra. 

 10. Bright red, unicolorous = var. rufa. 



a. var. pallida, Lampa. This is described as having a whitish-grey 

 ground colour. " The fore wings are pale greyish- white, with trans- 

 verse rows of black dots (just like silk moire), with fine and short 

 transverse lines." The original description is as follows : " Framvin- 

 garne blekgra, med tvanne tvarrader af svarta punkter, samt liksom 

 vattrade af sma och glesa tvarstrimmor : Sverige, Stockholm" 

 ( Entomologisk Tidskrift,' p. 72). 



j3. var. ccerulescens, mihi. I have a beautiful series of this 

 variety given to me, bred by Mr. Fenn, this year (1891), from Lee, 

 Kent. I have also specimens from Pitcaple, Hartley- Whitney, 

 Nottingham, Darlington and Hereford. This is apparently the var. 

 B of Guenee, who writes : -" Of an ashy-blue, much powdered with 

 blackish scales, and marbled with an infinity of striations of the same 

 colour, with all the lines, dots and markings of a deep blackish-brown. 

 The orbicular spot has, in my specimen, accidentally without doubt, 

 the form of a Z, and it touches the reniform, from which it is sepa- 

 rated only in the middle by a small blackish dot. I have received this 

 beautiful variety from England. Fig. 414 i of Engramelle resembles 

 it slightly " (< Noctuelles,' vol. v., p. 352). 



y. var. nebulosus, Haw. This reddish-tinted var. of instabilis 

 is thus described by Haworth : " Alis griseo-canescentibus strigis 

 duabus fusco-ferrugineis, alteraque postica e punctis tribus subtri- 

 angularibus." " In medio alarum primorum fascia fusco-ferruginea 

 seu grisea, in qua macula ordinaria, solo margine conspicua ; ciliis 

 maculatis. Alsd posticee grisescentes margine saturatiore : margo ipse 



