126 BIOLOGY AND ITS MAKERS 



Aristotle, who attempted, and in part indeed successfully, to 

 set up a larger number of groups. 



"But in his successors even more than in Linnaeus himself 

 we see the damage wrought by the purely systematic method 

 of consideration. The diagnoses of Linnaeus were for the 

 most part models, which, mutatis mutandis, could be employed 

 for new species with little trouble. There was needed only 

 some exchanging of adjectives to express the differences. 

 With the hundreds of thousands of different species of 

 animals, there was no lack of material, and so the arena was 

 opened for that spiritless zoology of species-making, which 

 in the first half of the nineteenth century brought zoology 

 into such discredit. Zoology would have been in danger of 

 growing into a Tower of Babel of species-description if a 

 counterpoise had not been created in the strengthening of the 

 physiologico-anatomical method of consideration." 



His Especial Service. Nevertheless, the work of Lin- 

 naeus made a lasting impression upon natural history, and we 

 shall do well to get clearly in mind the nature of his particular 

 service. In the first place, he brought into use the method 

 of naming animals and plants which is employed to-day. In 

 his Systema Natures and in other publications he employed 

 a means of naming every natural production in two words,, 

 and it is therefore called the binomial nomenclature. An 

 illustration will make this clearer. Those animals which had 

 close resemblance, like the lion, tiger, leopard, the lynx, and 

 the cat, he united under the common generic name of Felis, 

 and gave to each a particular trivial name, or specific name. 

 Thus the name of the lion became Felis leo, of the tiger Fells 

 tigris, of the leopard Felis pardus, of the cat Felis cairn ; and 

 to these the modern zoologists have added, making the 

 Canada lynx Felis Canadensis, the domestic cat Fells domes- 

 ticata, etc. In a similar way, the dog-like animals were 

 united into a genus designated Canis, and the particular 



