35 
I believe that almost every specimen of Arran Cidaria truncata (var. 
concinnata, Stph.) or Shetland C. immanata (var. pythonissata, Mill.), 
could be recognised at a glance. 
In P. albulata, one would like to be able to differentiate several 
races, somewhat as follows :— 
1. Ground-colour and hindwings white or whitish, markings dis¬ 
tinct, generally yellowish, size not dwarfed. This would cover most 
of the lowland specimens of the continent of Europe, except its most 
northerly part. 
2. Specimens similar to form 1 still prevalent, but with an 
admixture of more suffused examples, sometimes with the ground¬ 
colour and hindwings greyer or yellower, sometimes with the 
markings greyer. This would cover the ordinary English range of 
variation. 
3. Suffused specimens (yellowish-grey, etc.) prevalent, often weakly 
marked ; if strongly marked, with the markings more grey than yellow, 
culminating in almost melanic specimens, size reduced. This would 
cover the Shetland forms, and possibly those of some mountain districts 
in Scandinavia, etc. 
4. Small pale specimens prevalent, markings rather weak. Northern 
Norway. 
5. Very pale specimens prevalent, culminating in unmarked, white 
examples. Hebrides. 
Form 1 is certainly the type—“ Lilywhite, yellowish-striped 
geometer,” Sehiff. ( Schmett. Wien., p. 109); “ alis anticis niveis, . . . 
alis posticis . . . immaculatis,” Fab., Mant. Ins., ii., p. 212). The whitish 
continental examples would, I believe, be almost rarities in England. 
Yet many normal continental ones, such as Hiibner’s figure 257, and 
Duponchel’s plate cci., figure 2, or Freyer's plate 645, figure 1, would 
be normal also in many parts of England and Scotland. I do not 
propose a varietal name for these, but would define the type as having 
white or whitish ground-colour, and would give the same citations as 
does Staudinger, excepting niveata, Stph., Wood, which belongs to 
form 5 (ab. hebudiiini). 
Form 2 unfortunately cannot be named in its entirety, as it includes 
so many specimens agreeing with albulata, Hb., and a few even with 
the more extreme albulata, Sehiff. Haworth got hold of a specimen, 
or specimens, with somewhat infuscated hindwings and more greyish 
markings—“ al. ant. fasciis griseo-rufescentibus albisque alternis, 
strigaque alba undulatis communi in fimbria griseo-rufescente,” etc., 
hindwings “ fuscescent with whitish [fascia behind middle”_and 
Wood figures the same {lnd. Ent., fig. 698). Guenee received three 
males of the same from England, and this led him to make a “var. A” 
( Ur. et Phal., ii., p. 292) for the albulata of Haworth (p. 336), Stephens 
(iii., p. 299) and Wood (fig. 698), remarking that, at first sight, it looks 
specifically different from the type, and that it has only been found in 
England. The localities given by Wood {lnd. Ent., p. 109) are 
Battersea Fields, Epping Forest, and Meldon Park, near Morpeth. I 
have seen the form from Epping Forest and Darlington, and similar, 
but smaller, examples occur in Shetland. Staudinger, in 1871 {Cat., 
ed. 2, p. 190), named it qriseata, which name I should resuscitate for 
it. Form 2, then, consists of a blend of typical albulata with ab. 
qriseata, Stgr.; in my Darlington series, rjriseata, etc., preponderate. 
