TEPHROSIA CREPUSCULARIA AND T. BIUNDULARIA. 9) 
dark and well marked, but are not of so deep or rich a colour as 
those from Derby; but yet I believe in every case the black 
predominates over the brown. I believe, however, if our 
entomologists would keep distinct all specimens captured during 
March and the early part of April, and in the north up to the 
end of that month, from those captured during the month of May 
and June, and compare them, they would find a very considerable 
difference; and if in exchanging these species we were to get 
dates from our correspondents, we should be less liable to 
mistakes, and in time, by using a little discretion, get a fairly 
authentic series of these undoubtedly difficult species. 
Of course in a very early season, as in 1882, both species will 
occur earlier ; but the fact remains that the earlier 7. crepuscularia 
is nearly or quite over before 7’. biundularia puts in an appear- 
ance. It was so in that season when 7’. crepuscularia occurred 
at the end of February, and 7’. biundularia at the end of April; 
but there was no mistaking the species. It has often struck me 
that these two moths are sent away by entomologists to corre- 
spondents in mistake, as much through the discrepancies in the 
descriptions given in the ‘Manual’ and in Newman’s ‘ British 
Moths’ as from want of care in distinguishing them. No one, I 
think, can compare them without seeing how much at variance 
the descriptions are. Newman states in his description of 
T. crepuscularia, “ yellow-brown tinge; appearing in April”; I 
think this applies well to our earlier species, generally known as 
T. crepuscularia. Of T’. biundularia he says, “ grey ; occurring 
in April, and generally again in July”; yet says that “egos 
were laid by captured female from 21st to 27th of May;” thus 
proving the proper time of appearance to be the latter half of 
May. He further states that the larve hatched on 5th of June, 
but does not say that they produced imagines the same season. 
His description applies well, however, to our paler species 
occurring here at the end of May and beginning of June. Now 
what I beg to suggest is, that it is the earlier browner species, 
“ crepuscularia,” that is double-brooded. It is double-brooded 
in our Kent woods; and Mr. Ovenden, of Strood, has more 
than once bred the July brood; and I capture the second 
brood of 7’. crepuscularia every season in the woods near 
Rochester, within a week or two of the disappearance of 
T. biundularia from the tree-trunks. 
