208 RHE ENTOMOLOGIST'S RECORD. 
Commenting upon this report Riley says: ‘“‘ The swarming in the spring 
and fall of this large cosmopolitan butterfly has been frequently 
noticed and often discussed in entomological periodicals. It migrates 
to the north in the spring and to the south in the autumn. It seems 
to have been more than usually abundant this summer in this country, 
‘and, as a result, its migrations this autumn have been more frequently 
noticed than usual. We noticed, in the Cleveland Plaindealer of 
September 20th, a most interesting account of the passage of immense 
swarms over that city. The head lines of the article are so charac- 
teristic of American journalism that they will bear repeating :— 
‘MANY MILLIONS. Swarms of Butterflies Invaded Cleveland, and 
Everybody Gazed at the Wonderful Sight—A Beautiful Vision of 
Orange Yellow—Strange Flight of the Insects from North to South— 
Mistaken for Cholera “Germs—Immierants Who Disregarded Mayor 
Rose’s Proclamation.’ ”’ 
One other observation may be added, that of Bowles, who states 
that he has himself seen the shores of Lake Ontario, near Brighton, 
strewn with hundreds of their dead bodies, cast up by the waves, and 
which no doubt had formed part of a swarm, which from weakness or 
some other cause had perished while flying across the Lake. 
From these and similar observations it has been concluded that 
the swarming of this butterfly in autumn is analogous with that of 
birds before commencing their flight southward, and that,after swarm- 
ing, the butterflies return to the subtropical lands whence their 
grandmothers and greatgrandmothers set out in spring. It is admitted 
that the climate is such, in the northern territories to which the 
Species annually spreads, that the butterfly cannot possibly exist in 
the winter, and Riley, who first propounded the return theory, himself 
confesses that ‘“‘ under the most favourable conditions a ie majority 
perishes.”’ As we have said, Scudder accepts the theory as fact, and 
practically writes as if it were proved beyond question of dispute. For 
ourselves, although we know of no exact analogy among butterflies of 
a similar swarming habit, yet, in every other respect. the similarity 
between the habits of this species and our own European migrating 
species, Pyramets cardut, Colias edusa, &¢., 18 so great, both as to the 
continuous-brooded habit, and also as to Dr. Thaxter’s observation that 
the males and females in the autumnal swarms pair, that we are 
inclined to doubt the conclusion. It has never yet been shown that 
the journey has been successful. The swarms are somtimes noted as 
going in a different direction from that assumed by the theory, and 
much more evidence is necessary before even an approximation to 
success can be admitted. For ourselves, we doubt whether the return 
journey has ever been successfully made, and we consider that 
there is altogether insufficient direct evidence to warrant the asser- 
tion that the autumnal swarms of Anosia archippus migrate from 
the more northern parts of its summer range in America, to 
the south, in order to winter there. - Some of the quotations which 
we have just reviewed, and others anemibiemed by Riley (Zhird Ann. 
Rept. Insects of Missouri) and Scudder (Butterflies of New England) 
show distinctly that the swarms do sometimes fly more or less 
from north to south, or from north-east to south-west; but the 
general opinion that one is compelled to form, after reading most of 
the notes relating to the autumnal swarming of this species is, that 
