Wo THR 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 a,nd 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 autximn have been more frequently 

 noticed than usual. We noticed, in the Cleveland PlaindcaUr 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 joiirnalism that they will bear repeating : — 

 ' MANY MILLIONS. Su-arm.^ of ButtenlieH Jnradcd Cleveland, and 

 Everybody Gazed at the Wonderful Sight — A Beautifixl Vision of 

 Orange Yellow — Strange Flight of the Insects from North to South — 

 Mistaken for Cholera Germs — ^Immigrants 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 Avhile 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 Avhence their 

 grandmothers and greatgrandmothers set out in spring. It is admitted 

 that the climate is such, in the northern territories to Avhicli the 

 species annually spreads, that the butterfly cannot possibly exist in 

 the Avinter, and Riley, aa'Iio first propounded the return theory, himself 

 confesses that " under the most favourable conditions a large majority 

 perishes." As AA'e have said, Scudder accepts the theory as fact, and 

 practically Avrites as if it were proved beyond question of dispute. For 

 ourselves, although AA^e knoAV of no exact analogy among butterflies of 

 a similar SAA^arming habit, yet, in OA^ery other respect the similarity 

 between the habits of this species and our own European migrating 

 species, Pyrameis cardui, CoUas edtisa, &c., is 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 SAvarms pair, that Ave are 

 inclined to doubt the conclusion. It has never yet been shown that 

 the journey has been successful. The SAvarms are somtimes noted as 

 going in a different direction from that assumed by the theory, and 

 much more eAddence is necessary before even an approximation to 

 success can be admitted. For ourseh-es, Ave doubt AA^hether the return 

 journey has CA'cr been successfully made, and Ave consider that 

 there is altogether insuflicient direct evidence to warrant the asser- 

 tion that the autumnal swarms of Anoda archipjnis migrate from 

 the more northern parts of its summer range in iVmerica, to 

 the south, in order to Avinter there. Some of the quotations which 

 we haA'e just reviewed, and others mentioned by Riley {Third Ami. 

 Rept. Insects of Missouri) and Scudder {Butterflies of New England) 

 show distinctly that the SAA^arms do sometimes fly more or less 

 from north to south, or from north-east to south-Avest ; but the 

 general opinion that one is compelled to form, after reading most of 

 the notes relating to the autumnal SAvarming of this species is, that 



