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on T. biundularia and T. crepuscularia, being a résumé of the 
opinions of several entomologists of the country who up to 
the present time had turned their attention to this species 
(printed ‘‘ Ent. Record,” vol. ix., 1897, pp. I07—109, 142— 
144, I7I—175). 
In the discussion which followed Mr. South asked two 
questions :—(1) Did any character exist by which the species 
could be separated with absolute certainty? (2) Which was 
the commoner species? To the former no answer was 
forthcoming, but to the latter all members were agreed that 
T. biundularia was undoubtedly the more common, in fact 
the dominant form; while T. crepuscularia was everywhere 
very local, and very restricted in its distribution. Mr. Tutt 
said that T. crepuscularia did occur in Scotland, for some time 
since for three or four years in succession he had received 
considerable numbers from the neighbourhood of Perth. 
The specimens were of the Continental form, and the larve 
were identical with the English larve in every respect. 
These two could be broadly separated, and it was a matter 
of convenience to give them names. How else could we 
compare with Continental entomologists? No doubt here, as 
elsewhere among the Lepidoptera, we have examples of 
recent evolution,—in fact, species in the making. He 
instanced the experiments of Mr. Fletcher with species of 
Zygaena, and asked if we should lump them together because 
they freely crossed and produced perfectly fertile offspring. 
It would be most inconvenient to do so. He insisted that 
the comparison of dates in one year with dates in another 
year was worse than useless; it was absolutely misleading. 
He then referred to the ova, and stated that the ova of 
nearly all the Geometers had no characters by which they 
could be distinguished. Naturally the oval stage would be 
less modified than other stages, but added to this the group 
as a whole was in the oval stage the least modified section 
of the Lepidoptera. As regards the larve he disagreed, for 
both Mr. Bacot and the late Mr. Tugwell had shown broad 
distinctions in the later stages. In concluding he wished 
to express his high appreciation of the careful and impartial 
manner in which Mr. Hewett had put forward the evidence, 
and considered that from the study of closely allied species, 
as these were, more biological good would accrue than from 
the detailed examination of anisolated species. Mr. Barrett 
said that he possessed the drawings of Mr. Tugwell, and for 
his part saw but very slight distinctness in the larve,—in 
fact, only a shade distinction. In his opinion Mr. Hewett’s 
