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Show 4 ISLAND LIFE. [I'ART 1. practised ornithologist to tell the difference. If he is fon~ of insects he notices many butterflies and a host of beetles wh1eh, thouah on close exa.mination they are found to be distinct. from ours, 0 are yet of the same general aspect, and seem just what miaht be expected in any part of Europe. There are also of co;rse many birds and insects which are quite new and peculiar~ but these are by no means so numerous or conspicuous as to remove the general impression of a wonderful resemblance between the productions of such remote islands as Britain an<.l Yesso. Now let an inhabitant of Australia sail to New Zealand, a distance of less than thirteen hundred miles, and he will find himself in a country whose productions are totally uulike those of his own. Kangaroos and wombats there are none, the birds are almost all entirely new, insects are very scarce and quite unlike the handsome or strange Australian forms, while even the vegetation is all changed, and no gum-tree, or wattle, or grass-tree meets the traveller's eye. But there are some more striking cases even than this, of the diversity of the productions of countries not far apart. In the Malay Archipelago there are two islands, named Bali and Lombok, each about as large as Corsica, and separated by a strait only fifteen miles wide at its narrowest part. Yet these islands differ far more from each other in their birds and quadrupeds than do England and Japan. The birds of the one are extremely nnlikc those of the other, the difference being such as to strike even the most ordinary observer. Bali has red and green woodpeckers, barbets, weaver-birds, and black-and-white magpie-robins, none of which arc found in Lombok, where, however, we find screaming cockatoos and friar-birds, and tho strange mound-·building megapodes, which are all equally unknown in Bali. Many of the kingfishers, crow-shrikes, and other birds, though of the same general form, are of very distinct species; and though a considerable num her of birds are tho same in both islands the differen.ce is none the less remarkable- as proving that mere distance is one of the least important of the causes which have determined the likeness or unlikeness in tho animals of different countries. <JIIAr. I.] INTRODUCTORY. 5 In the western hemisphere we find equally striking examples. The Eastern United States possess very peculiar and interesting plants and animals, the vegetation becoming more luxuriant as we go south but not altering in essential character, so that when we reach the southern extremity of Florida we still find ourselves in the midst of oaks, sumachs, magnolias, vines, a:nd other characteristic forms of the temperate :flora; while the birds, insects, and land -shells are almost identical with those found further north. But if .we now cross over the narrow . strait, about fifty miles wide, which separates Florida from the Bahama Islands, we find ourselves in a totally different country, surrounded by a vegetation which is essentially tropical and generally identical with that of Cuba. The chango is most striking, because there is no difference of climate, of soil, Dr apparently of position, to account for it; and when we find that the birds, the insects, and especially the landshells are almost all West Indian, while the North American types of plants and animals have almost all completely disappeared, we shall be convinced that such differences and resemblances cannot be due to existing conditions, but must depend upon laws and causes to which mere proximity of position offers no clue. Hardly less uncertain and irregular are the effects of climate. Hot countries usually differ widely from cold ones in all their organic forms; but the difference is by no means constant, nor .does it bear any proportion to difference of temperature. Between frigid Canada and sub-tropical Florida there are less marked differences in the animal productions than between Florida and Cuba or Yucatan, so much more alike in climate and :so much nearer together. So the differences between the birds .and quadrupeds of temperate Tasmania and tropical North Australia are slight and unimportant as compared with the enormous differences we find when we pass from the latter .country to equally tropical Java. If we compare corresponding -portions of different continents, we find no indication that the almost perfect similarity of climate and general conditions has any tendency to produce similarity in the animal world. The .equatorial parts of Brazil and of the West Coast of Africa are |