supplies the innumerable stragglers which every year reach Bermuda and the Azores.
Insects.
Winged insects have been mainly dispersed in the same way as birds, by their power of flight, aided by violent or long-continued winds. Being so small, and of such low specific gravity, they are occasionally carried to still greater distances; and thus no islands, however remote, are altogether without them. The eggs of insects, being often deposited in borings or in crevices of timber, may have been conveyed long distances by floating trees, as may the larvae of those species which feed on wood. Several cases have been published of insects coming on board ships at great distances from land; and Darwin records having caught a large grasshopper when the ship was 370 miles from the coast of Africa, whence the insect had probably come.
In the Entomologists' Monthly Magazine for June 1885, Mr. MacLachlan has recorded the occurrence of a swarm of moths in the Atlantic ocean, from the log of the ship Pleione. The vessel was homeward bound from New Zealand, and in Lat. 6° 47' N., Long. 32° 50' W., hundreds of moths appeared about the ship, settling in numbers on the spars and rigging. The wind for four days previously had been very light from north, north-west, or north-east, and sometimes calm. The north-east trade wind occasionally extends to the ship's position at that time of year. The captain adds that "frequently, in that part of the ocean, he has had moths and butterflies come on board." The position is 960 miles south-west of the Cape Verde Islands, and about 440 north-east of the South American coast. The specimen preserved is Deiopeia pulchella, a very common species in dry localities in the Eastern tropics, and rarely found in Britain, but, Mr. MacLachlan thinks, not found in South America. They must have come, therefore, from the Cape Verde Islands, or from some parts of the African coast, and must have traversed about a thousand miles of ocean with the assistance, no doubt, of a strong north-east trade wind for a great part of the distance. In the British Museum collection there is a specimen of the same moth caught at sea during the voyage of the Rattlesnake,
