32 
and which comes so near some forms of unidentaria, that it is just 
possible it may prove to be not specifically distinct, or at any rate may 
have been the insect obtained by Piepers, and exhibited as ferrugata. 
In the British Isles, this species is less abundant, and more local than 
ferrugaria, Haw., and judging from the comparatively infrequent records 
of its red forms, and the constancy with which the black variety pro¬ 
duces its like, it seems that our climatic conditions are more than 
ordinarily favourable to the production of the black race ; for it appears 
that on the Continent, and in America, the red-banded forms are nearly 
or quite as frequent as the black. Even in our Islands, however, the 
former are by no means so infrequent as I supposed when I commenced 
these investigations, but are a good deal overlooked. I have seen 
examples from the North London district, Deal, Worthing, Isle of 
Wight, Weymouth, Exeter, Swansea, Rugby, Wicken, York, and from 
Co. Tyrone, in Ireland. Mr. E. A. Atmore also tells me that it is of 
general occurrence in Norfolk, and Mr. J. Collins that it is occasional in 
the Warrington district, while Mr. Harwood, as mentioned above, bred 
a few at Colchester. 
Concerning the range of the black form, it will be simplest to enu¬ 
merate the districts where it does not occur or is not common. Mr. 
Bankes reports that he has met with but very few in his district (Isle of 
Purbeck, &c.); Mr. Harwood that it “ does not seem generally common 
here ” (Colchester); Mr. Porritt that it “ does not occur in the Hudders¬ 
field district at all so far as I know ” ; Mr. Reid that he has never seen 
the insect alive and thinks, “ if it occurs in the North of Scotland, it 
must be either very local or very rare and Mr. de Y. Kane that his 
opinion is “ that unidentaria is much more restricted in Ireland than 
ferrugaria .” 
Habits.— Both species are generally double-brooded, appearing in 
May, and again in July and August.f I learn from two or three 
correspondents that they (or at least ferrugaria, Haw.) are probably 
normally single-brooded in the North. Mr. Harwood thinks that uni¬ 
dentaria belongs rather to June than to May, but my experience does 
not bear this out. In breeding, one often gets a partial third brood, or 
autumnal emergence, and last season, (1893), I observed a specimen of 
such in September, at Hale End. There is also a tendency, no doubt 
favourable to cross-fertilization, for some of a brood to lie over in pupa 
and join the next brood, or to emerge somewhat erratically at inter¬ 
mediate periods of the year. Both nearly always hybernate in the 
pupal state, but Mr. South had a curious experience with a brood of 
unidentaria in 1890-91, when four laggards of a brood from August ova 
hybernated as larvse, pupating at the end of March, and producing 
imagines a month later ( Ent ., xxiv., pp. 172-3). 
In many localities the two species occur freely together, but both 
Mr. Fletcher and Mr. Bankes have independently observed that uniden¬ 
taria seems to have a preference for somewhat moist localities, and 
though both are so common at San down that the point had never struck 
* Dr. F. B. ’White (Scot. Nat., iv., 173), records it as ‘-'not common” in 
Scotland, and only from three of his thirteen districts, “ Solway, Clyde, Tay.” 
f The spring brood often the finer and larger, and, according to some 
writers, much commoner than the summer brood, though Dr. hiding’s experi¬ 
ence is just the reverse in this respect. 
