46 THE PROBLEMS OF THE DEEP SEA n 



that tli8 attention of naturalists was powerfully 

 drawn to the wonderful differences between the 

 animal population of the central and southern 

 parts of the new world and that of those parts of 

 the old world which lie under the same parallels of 

 latitude. So far back as 1667 Abraham Mylius, 

 in his treatise " De Animalium origine et migratione 

 poj)ulorum," argues that, since there are innumer- 

 able species of animals in America which do not 

 exist elsewhere, they must have been made and 

 placed there by the Deity : Buffon no less forcibly 

 insists upon the difference between the FaunoB of 

 the old and new world. But the first attempt to 

 gather facts of this order into a whole, and to co- 

 ordinate them into a series of generalizations, or 

 laws of Geogi^aphical Distribution, is not a century 

 old, and is contained in the " Specimen Zoologic? 

 Geographicoe Quadrupedum Domicilia et Migra- 

 tiones sistens," published, in 1777, by the learned 

 Brunswick Professor, Eberhard Zimmermann, who 

 illustrates his work by what he calls a " Tabula 

 Zoographica," which is the oldest distributional 

 map known to me. 



In regard to matters of fact, Zimmermann's 

 chief aim is to show that among terrestrial 

 mammals, some occur all over the world, while 

 others are restricted to .particular areas of gi^eater 

 or smaller extent ; and that the abundance of 

 species follows temperature, being greatest in warm 

 and least in cold climates. But marine animals 



