56 THE ENTOMOLOGIST. 
sprung up from the north, and this must have caused tens 
of thousands of the butterflies and other insects to have 
perished. 
In the ‘Entomologist’ (vol. 1ii., p. 226) it is stated that during 
a cyclone, and a distance of 600 miles from the African 
coast and 200 miles from the Cape Verde Islands, a vessel 
was visited by numerous birds and butterflies, the latter being 
Diadema Bolina and Pyrameis Cardui. 
Now the instance related by Darwin only proves the fact 
of flocks of butterflies being observed ten miles from the 
land, and that recorded in the ‘ Entomologist’ leaves it an 
open question as to whether the insects were direct from the 
coast of Africa or Cape Verde Islands,* or indeed whether they 
occurred in remarkable numbers. We have, therefore, reason 
to believe that the vast host of Terias Lisa which arrived at 
the Bermudas on the lst of October last, and that visitation 
recorded in the ‘ Naturalist in Bermuda’ as occurring on 
the 10th of October, 1847, are the only instances known of 
such extraordinary flights of Lepidoptera, or indeed of any 
insects being met with at such an amazing distance from 
land. 
The question, therefore, naturally arises—How did this 
immense concourse of butterflies get to the Bermudas? The 
nearest point of land is Cape Hatteras, in North Carolina, 
which is somewhere about 600 miles distant, and if they had 
started from this point and taken a straight line to the islands, 
without meeting with any contrary winds, it would, at the rate 
of twelve miles per hour (a fair average rate of travel for any 
of the Pieride), have taken them two days and two hours (of 
course including nights) to complete the distance; a space 
of time almost too great, we should imagine, for an insect in 
no degree remarkable for robust frame or strength of wing to 
keep up a continuous flight. We are, however, inclined to 
think that the presence of this vast concourse of insects at 
the Bermudas was not owing to ordinary causes, and that we 
must look to some extraordinary means to solve the mystery. 
From a very extended series of observations made at inter- 
vals during the last twenty years, with the view of throwing 
light upon the migration of North American birds to those 
* I do not find any record of the occurrence of P. Cardui in the Cape de 
Verde Islands, although it is found on the islands to the north.--S. H, Scudder. 
