18 |June, : 
Migration of white Butterflies.—I believe it was at the end of August, 1849, 
that one fine Sunday morning I returned from Havre by steamboat. The air was 
perfectly still, and all pleasant and smooth above and below. A splendid flight of 
wild swans crossed our track, making for some place in Calvados I should think. 
Their double line in wedge-like form, with the dropping of the leader every moment 
or so alternately down to the rear of each line like a pearl strung on a thread, was 
a sight never to be forgotten. 
About mid-day, as we were all reading on deck, we seemed to plunge into a 
swarm, or snow shower, of common white butterflies, and so continued for nearly 
an hour. They literally covered us, circling round, and playing up and down the 
vessel, and I was struck with the fact, that they seemed to keep up with the vessel’s 
speed—about eight knots an hour—as well as to flutter up and down. 
Hither they flew at our pace easily, or were assisted by the air carried along 
with us in the calm. Gradually they thinned off, and a breeze arising, disappeared. 
At the same time an exhausted pigeon fell on board, and a thunderstorm on the 
English coast coming in sight, closed our pleasant Sunday trip with a beauty of a 
different kind. 
I noticed in the papers a few days afterwards, a paragraph about a large flight of 
white butterflies having crossed the Channel, and landed on the Hampshire coast, 
and thought I had seen them on the passage.—J. Crompton, Norwich, April, 1870. 
Note on Cossus ligniperda.—It is well known that the larva of Cossus ligniperda 
ejects from its mouth a colourless (or nearly so) strong scented fluid. I had always 
supposed this to be of a watery nature; but, having soaked up some of it with 
blotting paper and set fire to it, it burned as though it were turpentine or oil. 
Should this fluid prove to be of an oily character, it would be a very interesting 
fact. I write this note to suggest further investigation, as I do not meet with 
Cossus with sufficient frequency to follow the matter up myself.—T. AtGERNON 
Cuapman, M.D., Abergavenny, April, 1870. 
Notes on occasional second-broods in single-brooded Lepidoptera.—It is curious 
to note how some species of Lepidoptera, ordinarily single-brooded, are sometimes 
double-brooded. Thus, a second brood of Liparis salicis was met with in thousands 
on our sand-hills in Lancashire, in October, a few years since. The Ontario poplars 
on which the larvee fed in August and September are now all dead through defolia- 
tion by them. Again, a friend here bred several broods of Dasychira pudibunda in 
one year, the last brood appearing on and about Christmas day, the eggs from which 
hatched early next spring. I possess Orgyia gonostigma given to me by Mr. Machin, 
who told me they were of a third-brood in one season; and I have examples of 
Phragmatobia fuliginosa bred from eggs impregnated only thirty-five days before the 
perfect insects appeared; the female that produced these again paired with the same 
male, and laid a second batch of eges which I gave to a friend who bred insects there- 
from, but much later in the season; the same moths paired a third time, and the female 
again laid a batch of eggs, these continued a long time without hatching, but did so 
before the winter set in, and produced moths the following season. ‘The first batch 
of eggs were given by me to Mr. Edmondson, who fed the larve on lettuce ; the 
second batch I gave to Mr. Alexander Cooke ; aud the third 1 kept myself. The two 
