A HISTORY OF SCIENCE 



attention all the circumstances belonging to these dis- 

 coveries may allege also that the unknown quadru- 

 peds, whose fossil bones have been found in the strata 

 of the earth, have hitherto remained concealed in 

 some islands not yet discovered by navigators, or in 

 some of the vast deserts which occupy the middle of 

 Africa, Asia, the two Americas, and New Holland. 



" But if we carefully attend to the kind of quadru- 

 peds that have been recently discovered, and to the 

 circumstances of their discovery, we shall easily per- 

 ceive that there is very little chance indeed of our ever 

 finding alive those which have only been seen in a 

 fossil state. 



"Islands of moderate size, and at a considerable dis- 

 tance from the large continents, have very few quad- 

 rupeds. These must have been carried to them from 

 other countries. Cook and Bougainville found no 

 other quadrupeds besides hogs and dogs in the South 

 Sea Islands; and the largest quadruped of the West 

 India Islands, when first discovered, was the agouti, a 

 species of the cavy, an animal apparently between the 

 rat and the rabbit. 



" It is true that the great continents, as Asia, Africa, 

 the two Americas, and New Holland, have large quad- 

 rupeds, and, generally speaking, contain species com- 

 mon to each; insomuch, that upon discovering coun- 

 tries which are isolated from the rest of the world, the 

 animals they contain of the class of quadruped were 

 found entirely different from those which existed in 

 other countries. Thus, when the Spaniards first pene- 

 trated into South America, they did not find it to con- 

 tain a single quadruped exactly the same with those of 



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