PHYSICAL GEOGRAPHY OF THE WEST INDIES. 193 

 THE PHYSICAL GEOGRAPHY OF THE WEST INDIES. 



BY F. L. OSWALD. 

 III. REPTILES AND FISHES. 



THE present fauna of our planet includes many varieties of mam- 

 mals and reptiles, and a few kinds of birds, that are found only 

 on certain islands a fact which seemed rather to justify the once 

 universal belief in the origin of species by separate acts of creation. 



A different theory of explanation has, however, been suggested 

 by the discovery of fossil remains, proving the former existence of 

 closely allied forms on continents where their battle for existence had 

 to be fought against beasts of prey and competitors for a limited food 

 supply. 



The supposed products of an island genesis by the fiat of super- 

 natural agencies, demanding recognition in mental penance and the 

 payment of tithes, may thus be simply animal Crusoes, favored by 

 the positive or negative advantages of their surroundings. 



The dodo, in its struggle for survival, would have had no chance 

 against South American tiger-cats. Not one of the twenty-odd 

 species of Madagascar lemurs could have held its own against the com- 

 petition of the African daylight monkeys. 



Yet there was a time when night apes and large ground birds seem 

 to have had things all their own way, the world over, and Central 

 America may have afforded a chance for existence to several species 

 of reptiles which at present are found only on the West Indian 

 islands. 



The Cuban bush tortoise (Emys nigrd) is found only in the 

 forests of Santiago and Puerto Principe, and there only on the south 

 coasts. It is the most sluggish creature of its genus, and does not 

 seem to have had enterprise enough to crawl around the sand belt of 

 Cape Maysi and colonize the jungles of the north side provinces. It 

 is as helpless as a hedgehog, minus its bristles. The darkeys of the 

 Cuban planters crack its armor with home-made hammers, and the 

 tortuga prieta, or prieta, as they call it for short, forms a factor of 

 holiday menus as frequently as 'possum pie in southern Georgia. 



Swift-flowing rivers bear it away as they would a floating log, 

 and it is wholly incredible that its ancestors should have crossed the 

 Caribbean Sea in quest of a more congenial home; but it is possible 

 enough that its eggs may have been ferried across on one of the 

 driftwood islands which the Sumasinta River often tears from the 

 coast swamps of southern Mexico and carries into the current of the 

 Gulf Stream. The evolution of the South American giant cats was 



VOL. LV. 15 



