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president’s address. 
it had been captured as a rarity on several occasions prior to 1874, 
when I had the good fortune to take twenty-one, all males with 
one exception, by means of the attracting lamp. Since that time 
it has been captured in greater or less numbers by the same means 
every year, but is evidently far from common. During the past 
season, however (1891), it turned up at light in unusual numbers. 
The larva feeds on Sedge ( Cladium mariscus ), and is very beautiful, 
but little known and hard to rear. Lord Walsingham and Mr. 
Fletcher discovered it about twelve years ago but failed to prove 
its identity, though they had no doubt as to the species. This 
surmise has since been found to be correct, and the perfect insect 
has been bred more than once. But for its partiality to light the 
moth would very rarely be taken. 
There are many other insects belonging to the “ old fen ” group 
which it would be interesting to treat individually, but I only propose 
to mention one more, whose claim to notice rests not so much upon 
any imminent risk of extinction, as upon the singularly meagre 
nature of the published accounts of what is to the fen collectors 
a very well-known insect. Tapinostola helmanni, a species nearly 
allied to concolor, was taken at Yaxley by Mr. Bond in 1847, and 
afterwards in some numbers by other collectors. 
When I first met Mr. Brown at Cambridge he informed me 
that the insect was then only to be met with at Monkswood, if 
indeed it still lingered there ; and, in fact, no captures appear 
to have been made for several years before that time (1872). 
When therefore, in the same year, I found some species of 
Tapinostola — which was new to me — fairly common at Wicken, 
I concluded that my captures were T. concolor, of which species 
I had then no details, while the published descriptions were to my 
inexperience utterly insufficient to distinguish them. On comparing 
them, however, with the types in the collection of the Anatomical 
Museum, I soon discovered the mistake ; and, in my subsequent 
experience of Wicken, found it to occur regularly, and in consider- 
able plenty. I mentioned the matter to Mr. Bond, and heard, in 
reply, that he had himself discovered it at Wicken, and had bred 
it from a larva feeding internally in the upper part of the reed, 
