THE ANIMAL WORLD OF BRAZIL 



— which are apparently identical with the European species, and 

 others which are quite different. The first are North American 

 butterflies, and the second South American. 



What the animal life of our own period tells us is confirmed by 

 the animal life of primeval ages. The earlier forms of Elephant 

 which lived in North America when the northern areas had a warmer 

 climate prove that these pachyderms moved round the North Pole 

 in periodic migrations, and that there was no obstacle to their 

 passing from America into Europe or Siberia. The separation of 

 these continents by the sea cannot, therefore, be of very ancient 

 date ; ancient, that is, by the historical standards of the world of 

 animals. For many geological ages the northern hemisphere of our 

 planet seems to have been covered by an unbroken area of land, 

 joining North America, Europe and Asia, while bridges of land 

 connected Europe with North Africa by way of Gibraltar, Sicily, 

 and the Greek Archipelago. 



Turning to South America, we find that the American Mediter- 

 ranean is much wider than the sea dividing Europe from Africa: 

 the West Indies must not be regarded as a bridge, for in their 

 formation they are equally remote from the two continents; and 

 the same holds good of Central America, which seems at one time 

 to have consisted of islands. As for the Isthmus of Panama, only 

 36 miles in width, it was first formed when both continents had for 

 untold ages led an independent existence, and had developed an 

 abundant flora and fauna. This is confirmed by the geologists and 

 the zoologists alike, and by the comparison of the marine animals 

 on either side of the isthmus. 



Thus a family of corals, Fungia, is at home only in the Pacific 

 and Indian Oceans, but one species extends into the Caribbean 

 Sea. How can it have come thither, save from the west? Similarly, 

 in the sea to the east of the Isthmus of Panama there are a number 

 of sea-anemones which are unknown in other parts of the Atlantic, 

 but have their home in the Pacific. Similar forms of sea-urchins, 

 too, prickly, globular creatures which move by means of tubular 

 sucker-feet or pseudopods, are found on both sides of the isthmus ; 

 and so is a species of crab, Hippa eremita. Lastly, of 374 species of 

 coastal fish inhabiting the Gulf of Panama, no less than 54 are 

 found on the West Indian side of the isthmus. 



South America is essentially a continent of the southern hemi- 

 sphere ; of all the continents it reaches farthest towards the South 

 Pole. It rose out of the water at a very remote period. Its foundation, 



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