17 
August. The insect remains in the pupal stage about six or eight weeks 
before emergence. 
The species is well distributed in our southern and western 
counties, but does not appear to be taken anywhere commonly in the 
autumn. Earely is it ever found at rest, but a few appear at the ivy 
blossom under favourable conditions. Birchall records it from County 
Wicklow, but I do not believe it has yet been recorded from any Scotch 
localities. Most of the specimens in our cabinets are bred from ova, 
which have been supplied by Dr. Chapman from Hereford, or by the 
Lewes collectors. Staudinger gives as its range on the Continent:— 
“ Central Europe (except the Urals); Southern Sweden (?) ; N. Italy ; 
Spain; N. Balkans.” 
Xantkia citrago. —This species appears to have nothing in common 
with flavago and fulvago , which I look upon as the true types of the 
genus Xanthia. I have previously mentioned the strange fact that the 
terminal segment of the pupa in no way resembles either of the groups 
with which it is usually allied, that is, with those Orthosidce like Glcea, 
or, on the other hand, with those Orthosidce which come near the 
Hadeiiidce like Tceniocampa ; in fact, Dr. Chapman calls my attention to 
its similarity in this respect to Cuspidia (Acronycta), although I do not 
mean to suggest that it has any close affinity with Acronycta from this 
isolated fact. At the same time there is no doubt from its general 
characters, habit of the larva, pupal structure, different arrangement of 
transverse lines, etc., in the imago, that the moth has no very great 
affinities with those species with which it is at present grouped. 
Xanthia citrago is distinctly of two shades of colour—a pale orange, 
almost yellow, and a rich orange approaching the colour of croceago , in 
fact, one specimen kindly given to me by Mr. Holland quite equals 
that species in intensity. This coloration is to a certain extent sexual, 
for whilst a large number of the males and all the females are of the 
paler tint, a small proportion of the males are of the darker orange 
coloration ; not that there is any very distinct line of demarcation, but 
the males are certainly dimorphic, or, at least, have a strong dimorphic 
tendency, the females (at least, not in the large number of specimens I 
have) certainty not exhibiting this difference in anything like so 
marked a degree, or, in fact, at all. This dimorphic tendency in the 
males is accentuated by the development in most of the richer coloured 
specimens of a distinct, well-marked, dark fascia crossing the centre of 
the wing between the stigmata, the fasciated appearance being due to 
the widening of the normally fine central line by a shading of fuscous 
scales on its outer edge and its union with the reniform, which in these 
specimens also partakes of a fuscous hue. All my extreme, strongly- 
marked specimens are, without exception, males. One specimen to which 
I have before referred, is very striking, not only from the richness of 
the ground colour, but from the fact that outwards from the elbowed 
line it is so suffused with dark scales as to have the appearance of an 
outer band, as is so common in X. aurago. This, perhaps, shows simply 
a tendency to produce a common form of variation for purposes of pro¬ 
tection, as this specimen of citrago came from Beading where the 
banded form of aurago is very abundant. The pale yellow form of 
this species is the type, the richer coloured orange form being known 
as var. aurantiago, whilst that in which the central line becomes fascia¬ 
ted is the subjiava of Eversmann recorded by Staudinger from “ Ural 
D 
