THE 
WEEKLY ENTOMOLOGIST. 
“ ENTOMA etUIDQUID AGENT NOSTIil EST FARRAGO LIBELLI.” 
No. 9.] SATURDAY, OCTOBER 11, 1862. [Price 2d. 
IMMIGEATION. 
our hist number appeared a 
highly interesting communication 
from a well known Entomologist, 
G. E. Mathews Esq., of Weymouth, 
headed “Captures at Sea,” where 
the writer remarks, that it is not at 
all improbable, that novelties which 
have occurred in the South of 
England within the last few years, 
might have immigrated by crossing 
the channel. Of course we must 
suppose our correspondent refers to 
well known South European species, 
* 
such as Polyommatus Bccticus, Pieris 
Baplidice Sfc. We should not for a 
moment think of controverting this 
theory, supported as it is by evidence 
of no inconsiderable value. We may 
however perhaps be allowed to hint 
at a few questions, which appear to 
suggest themselves. In the first place 
let us consider what qualifications an 
insect must possess, in order to enable 
it to traverse a distance of more than 
twenty miles by sea, supposing it to 
take the shortest possible cut from C. 
de Gris Nez to Dunge Ness. The 
most notable instance of a migratory 
insect is doubtless that of Gryllus 
Migratorius. 
The distance this insect will fly 
across the open sea is, we suppose, 
almost unlimited. No one who has 
seen this well-known insect can have 
failed to remark, liow peculiarly the 
wings are calculated for long and 
continuous flight. Now strange to say 
the Genus Pieris is by no means 
remarkable for strength or rapidity 
of flight, and in that Genus, Bap- 
lidice in particular, is singularly 
sluggish in its movements. Among 
the Lycocnidce some species indeed are 
known to be very quick on the wing, 
but have never been observed to fly 
very high or for a long distance. We 
have watched Theda Betulce more 
than once, flying gently and easily 
along a hedgerow, but never going 
very far without alighting on a twig. 
But to come to the genus Polyommatus 
itself, who has not seen Alexis dancing 
amo'ng the long grass in some sunny 
meadow ? Have not most of us too, 
remarked the flight of Cory don, 
Adonis, Agestis, Alsus and vEgon? 
How strange it would appear to us to 
see any of these species flying high 
above our heads from the deck of a 
Folkestone Steamer ! We should 
remember however that what an 
insect is in the habit of doing is no 
