MIGRATION AND DISPERSAL OF INSECTS: LEPIDOPTERA. 13 
Migration and Dispersal! of Insects: Lepidoptera. 
By J. W. TUDT, FHS: 
We have already shown that butterflies and moths have often been 
observed and captured at considerable distances from land. The habit 
of flying out to sea is probably much more frequent than is generally 
supposed. Walker reports that at Colombo, on April 20th, 1890, the 
forenoon being fine and hot, quite a number of butterflies came off and 
flew about the ship, but they were wild and difficult to approach. 
Among these several male specimens of Ornithoptera pompetus were 
recognised (one secured), Papilio sarpedon, P. pammon, P. diphilus, P. 
polynnestor, Messarus erymanthis, &. Mr. Manger has an example of 
Macroglossa stellatarum taken in the Red Sea, one of Patula macrops in 
the Straits of Malacca, ten miles from land, in June, 1894, an Ophideres 
fullonica in the China Sea, 100 miles from land, both the latter by Cap- 
tain Walker, Deilephila alecto, that came on board thes.s. Mallard in the 
Mediterranean, Deilephila livornica and Chocrocampa celerto captured in 
the Red Sea, Abraxas phantes off Cochin China, 100 miles from land, 
in June, 1894, Huchera capitata taken in the China Sea, on the 
Kara, in July, 1894, by Captain Walker, and Maryarodes unionalis 
captured off the coast of Algiers. We ourselves saw a specimen of 
what appeared to be Pieris rapae heading straight for the coast at Folke- 
stone, as we were crossing to Boulogne on July 26th, 1899, when the 
boat was about halfway across the Straits, and there is a note (Hntom. 
Record, xi., p. 297) of Pyramets atalanta having been captured (many 
seen) in the Atlantic Ocean, some 500 miles from the Lizard. These, 
however, are more or less isolated examples, and it may be well to 
review the evidence available of larger or smaller flights of lepidoptera 
that have been observed on what must certainly be considered migration 
flights. 
Kapp observes (Naturforscher, vi., 111) that on a calm sunny day he 
noticed a prodigious flight of Peris brassicae, that passed from north- 
east to south-west, the flight lasting two hours. Kahn also records 
(Travels, i., 18) a flock of this species about halfway across the English 
Channel. Tindley writes (Roy. Milit. Chronicle, 1815, p. 452) that in 
Brazil, at the beginning of March, 1808, there was, for many days 
successively, an enormous flight of white and yellow butterflies, prob- 
ably of the same tribe as the cabbage butterfly; they were never 
observed to settle, and proceeded in a direction from north-west to 
south-west, no buildings seemed to stop them from steadily pursuing 
their course, which, ‘‘ being to the ocean, at only a short distance, they 
must have reached to perish.’’ A migratory column of Pyramets cardut, 
of from 10ft.-15ft. in breadth, was observed in the Canton Vaud 
(Switzerland), in 1836, the flight occupying two hours on its passage. 
The reports of the lighthouse keepers, furnished to a committee 
appointed by the British Association for the advancement of Science, 
show some very definite results. Some of the extracts taken from them 
are as follows :— 
Hanois Lighthouse (to the west of Guernsey), the extreme westerly point of the 
Channel Islands, in a direct line between the N.W. coast of France and the S.W. 
coast of England. 1882.—‘‘June and July: Flights of Plusia gamma.” 1885.— 
“September 13th: Wind §S.E., sky cloudy. Silver Gamma moths all evening round 
lantern.’ 1886.—‘‘October 31st, 8.0 pm. A quantity of Silver Gamma moths 
also a few brown ones but smaller than the Gamma.” 
