A NATURALIST IN BRAZIL 



of life. The larger birds cover the widest expanse of water; the 

 Virginian plover, for example, on its spring and autumn migrations, 

 flies from Labrador to Venezuela and back again; the Stork of 

 East Prussia migrates to South Africa ; the Fish-eagle and the Egret 

 are citizens of the world, and the Barn-owl is no less valiant a 

 traveller, though one would never have expected it to cover such 

 vast distances. And involuntary journeys of considerable length are 

 often made by birds caught in a gale. No less than 46 species of 

 American birds have been wafted over to England, while 37 Euro- 

 pean species have reached North America. The bird-watcher Gatke 

 found on Heligoland 15 species of American land-birds. 



In the same way German dragonflies and butterflies are often 

 borne on the wind from Germany to Heligoland, and even to 

 England. And even among the butterflies there are world-citizens; 

 I myself found the Painted Lady on the highest mountains in 

 Ceylon, and on the Tijuca peak near Rio. This pretty butterfly was 

 like a greeting from my home. A Hawk-moth, Celerio linata, which 

 dashes through the air on its narrow wings, has made itself at home 

 in every continent, and the black and brown butterfly, Danais 

 erippus, has in our own day invaded Polynesia (1863) ayad Celebes 

 (1873), and in the other direction has reached the Azores, and 

 according to Sietz is occasionally seen in the British Isles. 



Many living creatures may be carried across the sea on drifting 

 wood. A huge snake, a Giboia, a native of America, was once driven 

 ashore on the island of St. Vincent ; it had wrapped itself round a 

 tree-trunk, and was full of life. The fauna of the Polynesian islands 

 has been frequently enriched by insects, snakes, and even (it seems) 

 by mice, which have reached the islands on driftwood. The patches 

 of woodland along the shores of La Plata harbour a whole series of 

 insects, frogs, and snakes of northern origin, and large snakes, 

 crocodiles, and even jaguars have drifted as far south as Buenos 

 Aires on the trunks of trees. On a floating tree in the Amazon, 

 Spix and Martins saw a troop of monkeys ; on another, squirrels, 

 and on a third a tiger-cat and a crocodile. Those who, sailing along 

 the Brazilian coast, have seen how far from shore the brown waters 

 of the Sao Francisco are distinguishable, will readily believe that 

 many an animal may drift seaward on a floating tree, until it becomes 

 the plaything of the ocean currents, to be stranded finally on some 

 distant coast. 



But the fauna of South America teaches us that a greater exchange 

 of species must have taken place than can be explained by these 

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