9 
Stenopteryx noctuella as instances of migratory insects in connection 
with the subject for discussion. Also a specimen of Rhizoyramma 
detersa, found amongst British lepidoptera in a purchased store box. 
The usual habitat of this insect was stated to be Southern and South 
Central Europe, but Mr. Prout thought it possible that the specimen 
was taken in this country as a casual migrant. 
Hydrilla palustris from Carlisle.— Mr. G. B. Routledge, a 
male specimen of Hydrilla palustris, taken by Mr. G. E. Thwaytes, 
near Carlisle, on June 6th, 1899. The insect was taken with the net, 
in the same locality as were two female specimens, captured by Mr. 
F. H. Day. 
Habits of Senta makitima.— Mr. E. M. Dadd recorded the 
capture of larvae of Senta maritima in large numbers near Berlin. 
They were found in reed stems that had been previously eaten out by 
larvae of Nonayria yeminipuncta. Mr. Dadd announced that, in the 
opinion of German entomologists, the lame of S. maritima did not 
feed on the reeds, being entirely cannibalistic, and preying upon living 
lame of Heliophila obsoleta, on spiders, or any other like food which 
they could obtain. 
Discussion, Migration of Insects. —A discussion on migration of 
insects was held. Mr. Prout, in starting the discussion, referred to 
Plusia yamma as an example of a regular and constant migrant, and 
remarked that it was curious that there were no records of the obser¬ 
vation of large flights of this insect. Mr. E. M. Dadd instanced Cara- 
drina ambiyua, Heliophila albipuncta, and Aporopkyla lutulenta as 
migrants which were formerly rare and now were gradually spreading. 
From inquiries made at Berlin it appeared that C. ambiyua was now 
more commonly met with than formerly. //. albipuncta had, how¬ 
ever, always been plentiful there. Mr. A. Bacot expressed the opinion 
that the fact that an insect becomes more common does not prove 
that it is spreading. It may be a case of periodicity, a suggestion 
supported t by the appearances of Eurymus croceus. Mr. -J. W. Tutt, 
who spoke at some length on the subject, said that no one can state 
positively if an insect does or does not occur in certain districts. In 
support of this contention he referred to Oeunistis quadra, which, after 
being to all appearances extinct for many years, suddenly occurs in 
thousands in the New Forest; also to Plusia chryson, of which only 
eleven British specimens were known until Warren found one larva 
and subsequently took 750 in the same year, and the insect is now 
found in very many localities by those who know how to look for it. 
From these and other instances Mr. Tutt drew the deduction that in 
almost every case the insect had been overlooked. He, however, 
excepted Plusia mvneta, which had probably been introduced a long 
while ago, and had recently multiplied under favourable conditions. 
Mr. L. B. Prout contested this theory so far as < 'aradrina ambiyua 
■was concerned, as he was positive that this insect, which had recently 
appeared at Sandown, I.W., had not been overlooked by him in recent 
years. Other speakers referred to Leucoma chrysorrhoea, Stilpnotia 
salicis, TJeiopeia pulchdla, and Orthosia suspect a as actual or probable 
migrants. 
April 2nd, 1901.— Cases of Luffia ferchaultella, etc. —Dr. 
Chapman exhibited cases of Lufia ferchaultella and a small spider 
