TAXONOMY 



261 



species of animals are related to one another through common descent. 

 Classification may now insure the convenience that was desired in the 

 earliest attempts at organization, and at the same time express the kin- 

 ship which the evolution doctrine implies. The advantages of a system 

 which serves this double function are so great that it is now recognized 

 that there can be but one true and natural basis for taxonomy, and this 

 lies in the genetic relations and the successive steps of divergence from the 

 more or less generalized types. Far, then, from being a mere cataloging 

 or describing of animals, systematic zoology is concerned with the estimat- 



FiG. 202. — Carl vod Linne (Carolus Linnaeus), 1707-1778, at the age of forty. {Courtesy 



of New York Botanical Garden.) 



ing of the relative importance of all structural details, the habits, and 

 the distribution of the forms, as evidence from which the pedigrees may 

 be reconstructed and expressed. 



Ray and Linnaeus in Taxonomy. — It has been said that John Ray 

 (1627-1705), an Englishman, was the first true systematist. Ray pro- 

 posed a dichotomoiis systematic table of the animal kingdom, that is, 

 a system which branched by twos, and distinguished by anatomical 

 characters several groups now recognized as natural ones. It is Carolus 

 Linnaeus (Carl von Linne, Fig. 202, 1707-1778), however, who is con- 

 sidered to be the real founder of classification. Linnaeus's most important 

 work was the Systema Naturce which appeared in twelve editions between 



