ASSOCIATIONS AND MIGRATIONS. 101 
the purpose of rearing, by their united labour, a 
comfortable dwelling. 
There have been instances of butterflies associating 
in large bodies: but for what purpose, no one has as 
yet been able to ascertain. We are informed by Mr 
Knapp, that on a calm summer day he observed a 
prodigious number of the Papilio Brassice, or Large 
Cabbage Butterfly, flying from north-east to south- 
east ; and so immense were their numbers, that their 
flight was continuous for upwards of twohours.* And 
Kalm relates in his T'vavels,t that he noticed this 
remarkable flight nearly halfaeross the British Chan- 
nel. It is recorded by Lindley, in the Royal Mi- 
litary Chronicle, that in the beginning of March 
1823, in Brasil, there were prodigious flights of white 
and yellow butterflies, which lasted for many days 
sucessively. They were not observed to settle any 
where, but proceeded on their course from north-east 
to south-east. So direct was their line of travel, that 
nothing stopped them ; and their progress was to- 
wards the sea, which was not far off, where they, 
in all probability, would perish. Itis curious, that, at 
the time this flight was observed, no other species 
could be seen ; and this is the more remarkable, as 
the country abounds in a variety of these insects. 
“An extraordinary flight,” says Captain Adams, 
“ of small butterflies, with spotted wings, took place 
* Rosex’s Amusements of Insects, ii. 135, 
+ Karm’s Travels, p. 13, 
