EFFECTS OF TEMPERATURE ON INSECT DEVELOPMENT. 139 
larvee of Vespa vulgaris), I have met in each case with a single 
instance of their appearance in such unusual numbers in circum- 
stances of unusually raised temperature, or protection from 
external influences, that perhaps some of the details may be 
worth noting. 
The Clythra quadripunctata is said, by Stephens (Brit. Ent. 
iv. 354), to be not uncommon in certain places within the 
metropolitan district; but at Sedbury, in West Gloucester- 
shire, where I found this beetle in great numbers towards the 
end of April, 1872, I had only seen two specimens previously, 
though the fir wood abounded with nests of the wood ant, and I 
was in the constant habit of observation. The nest from which 
the Clythra appeared was quite exceptional in size, being nine 
paces, of nearly a yard each, in circumference, and was formed 
(not in or on a decayed stump) simply of sticks and rubbish piled 
in a great heap on the grass just outside the wood, where it 
was exposed to rain and (during about half the day) to sun- 
shine. 
On the 24th of April I found the Clythra in great numbers, 
mostly in pairs, on the grass by the nest; and they continued 
to appear so numerously on that and the following days that I 
took thirty at a time, and returning again and again at short 
intervals, found them still appearing—far more than I cared to 
take. Being desirous of making out the locality of the larve 
and pupe, I went to the nest about 10 a.m., before the ant-cocoons 
had been brought up for the day, and, opening the mass carefully 
downwards with my hands till I came to what may be termed the 
nursery of the nest, there, amongst the ant-cocoons and larve, 
I found the flask-like cocoons of the Clythra in great numbers, 
formed, as far as I was able to judge by their texture, of minute 
morsels of the surrounding matter (chiefly vegetable débris from 
small sticks) glued together by the larve. Some of the beetles 
were still not advanced beyond the larval stage, lying curled like 
small cockchafer grubs in their cases; and, from the much- 
enawed state of a few of the ant-cocoons after the beetle larve 
had been confined amongst them for a night, I conjecture Clythra 
quadripunctata, in its larval state, to be carnivorous. Kaltenbach 
(‘ Pflanzenfeinde,’ p. 612) mentions that the larva of this species 
is, according to Dr. Rosenhauer, found in ants’ nests, and is 
“fostered there by the ants’’; but as far as I could judge from 
