216 [September, 



Distinction of Argyro2)locc sellana,Hb. — In Staiidinger's European Catalogue 

 this is included as a simple synonym of ohlongana, not even ranking as a variety. 

 I used to take sellana commonly in the Madingley Chalkpit near Cambridge, but 

 have never met with it in Wilts, where ohlongana is fairly common, and have 

 never had any doubt of its distinctness ; but the different shape of the fore- 

 wings (in sellana the costa is more arched and the termen less oblique) is 

 probably not appreciated by everybody, and though the whitish hind-wings of 

 ohlongana g are really a reliable distinction, there is some variability in the colour 

 of the hind-wings of both species, and it was quite possible to argue that the 

 difference was varietal or geographical. In this genus, however, there are often 

 good specific characters in the secondary sexual structures of the S > which have 

 been much overlooked, and on making search for such I found that in sellana S 

 on the under-siu'face of hind-wings the tornus and lower part of dorsal area is 

 clothed with long, rather rough, whitish hair-scales suffused with pale yellow ; 

 this structiu'e and the yellow coloiu- are not found either in ohlongana or gentia- 

 nana, and I think should be conckisive. I may add that all three species are 

 fvu-nished in the J with an expansible hair-pencil from the base of posterior 

 tibiae above. European and Algerian examples of these forms agree essen- 

 tially with British. — E. Metrick, Thornhanger, Marlborough : Aug. 7th, 1910. 



Times of emergence of British Lepidoptera. — With reference to Mr. R. M. 

 Sunley's interesting note {antca p. 194) on the time of emergence of New 

 Zealand Lepidoptera, and his request for information from entomologists of 

 other countries, I may mention that, dui-ing the last thirty years, I have reared 

 an enoi-mous number of species of British moths, varying in size from Manduca 

 atropos dovm. to Nepticula acetossa, and often in very lengthy series. During the 

 last eleven years, the attempt, which was previously impossible, has been made 

 to inspect my breeding-cages fairly freqiiently each day at the right season, 

 and to take down detailed notes of the precise, or approximate, times of 

 emergence of the imagines, and many species, representing various groiips, 

 have been dealt with in this way. Speaking from memory, I shovild say that an 

 appreciable majority of the British moths, that have been under observation, 

 have left the pupa during the hoiu's of daylight, and not of darkness, and, in 

 any case, large numbers of them have certainly done so. My experience has 

 also made it clear that, whereas some species almost invariably emerge during 

 a special period, restricted, perhaps, to two or three hours, others seem to do so, 

 quite indifferently, at any hour of the day or night. And between these two 

 extremes, one finds every possible intermediate class, the members of one 

 displaying greater regtdarity, and of another greater irregularity, of habit. 

 But most of the imagines reared have exhibited a more or less marked 

 preference for emerging diu'ing some special period, whether longer or shorter, 

 of the twenty-four hoiirs, and it is highly improbable that, in tliis respect, 

 their behaviour in confinement differs from what it would be in natiu-e. One 

 might perhaps suppose that emergence would take j^lace, as a rule, just 

 sufficiently long before the usual time of fiight for the wings to become 

 thorovighly dry by then, bixt although this appears to be the case with some 

 species, others are fully eqviippcd for flight many hoiirs before they would 

 natiirally come on the wing. 



