18 
past been taking a deep interest in the Geometrid moths known in this 
country, after Haworth, as Coremia ferrugnta (or ferrugarid) and uni¬ 
dent aria* 
All through the history of entomological nomenclature there has 
been a recurring tendency, on account of their great superficial similarity, 
to unite these two as one species, and it was the desire to obtain in¬ 
dependent evidence on the question of the identity or distinctness, by 
breeding both forms from the egg, which first led me into the study of 
them. Being at that time quite a novice in entomology, I was unaware 
of the careful breeding experiments of Messrs. C. Fenn, Sydney Webb, 
and others, including our own member Mr. Boden, but even had it been 
otherwise, there was the conflicting statement in Newman’s “ British 
Moths,” that Sepp had “ figured both varieties as bred from the same 
caterpillar ” (or, as it should perhaps be stated, “ from the same batch 
of eggs ”), and also the experience of so excellent an observer as Mr. 
Nelson M. Richardson, that he had obtained one form from eggs of the 
other; from which it was evident that further investigation was 
required. 
After breeding each species several times, and having the good 
fortune to abundantly verify Newman’s statement that “ Coremia uni- 
dent aria occasionally has a purple-red median band, very much resembling 
that of C. ferrugata ”—a fortune which has not yet attended Messrs. 
Fenn and Webb, in their far greater experience, and communicating 
with several entomologists who had information to impart on the 
subject, I wrote a somewhat tentative article, which appeared in the 
Ent. Bee. of July, 1892 (vol. iii., p. 150). My own personal opinion 
was at that time, what has since been proved correct, that we had two 
quite distinct species to deal with, and that the seeming contradictions 
were to be reconciled through the existence of a red form of unidentaria, 
Haw. so like ferrugaria, Haw. as readily to be mistaken for that 
species. It is, indeed, somewhat surprising, that so much uncertainty 
and confusion still prevail; for I find that Doubleday, 30 }mars ago, knew 
pretty well as much about the state of the case as any of us know to-day. 
This is proved by Newman’s note in the Entomologist Tor H61-5 (vol. ii., 
p. 19), as well as by the material our great entomologist has left behind 
him in his collections. Dr. Ivnaggs (Ent. Ann., I 860 , p. 100), also 
writes that “ Mr. Doubleday has pointed out to me excellent and constant 
distinctive characters which exist in the hind wings of the perfect 
insects; thus in C. ferrugata, the hind wings present a more or less 
mottled appearance from greater contrast between the ground colour 
and markings, while in C. unidentaria they have a confused, somewhat 
unicolorous look: the darkest shading of the hind wing in C. ferrugata, 
is at the hind margin, which is, as it were, deeply bordered, but in C. 
unidentaria, on the contrary, the base of the hind wing is the most darkly 
shaded part—the transverse lineations across the middle are much more 
strongly marked in C. ferrugata than in unidentaria, Ac., Ac.” 
“ The above distinctions between these species hold good, even when 
specimens closely approximating in colour are opposed, so that this 
question may now be looked upon as settled.' ’ The closing italics are mine ; 
* Throughout this paper except in dealing with variation, I have called the 
species by Haworth’s names, by which they are universally known to .British 
entomologists. 
