LANDMARKS OF BOTANICAL HISTORY GREENE 24 1 



that some authors began with the highest and proceeded to the 

 lowest, and that other authors, beginning with the herbaceous 

 genera, ended with the ligneous, the largest and most enduring trees 

 coming last of all. This last is the order followed by Tragus; not, 

 however, as one philosophically viewing the plant world from lowest 

 type to highest as a genetically connected whole. It is, on the con- 

 trary, quite certain that that Aristotelian idea, only now very lately 

 reinstated, never entered Tragus' thought at all. If he takes up 

 herbaceous plants first in order, it may well be because they are 

 both the most numerous as to the genera and species, and of the 

 highest importance to man. Nevertheless we shall find him very 

 much given to running like things together and thus forming groups 

 within groups, lesser ones within the more comprehensive, whether 

 he be dealing with herbs or with shrubs or with trees. This is 

 taxonomic work; and this is the way in which he fulfils the promise 

 made in his Preface about natural arrangement. We must follow 

 him now for some distance, and very carefully, if we are to arrive 

 at an understanding as to what botanical system really was, in 

 Germany, in this first half of the sixteenth century. 



In no author as early as Tragus is there given any introductory 

 S5Tiopsis or tabulation of the system. Such convenient and helpful 

 skeletonization is a later invention; and here one gathers informa- 

 tion about the system, even to the principles that underlie it, 

 only through following the author chapter by chapter from the 

 beginning of the volume to its end. 



For a work like this, of 1200 pages, the selection of 100 for such 

 analytic study must suf&ce. They might be taken at random from 

 any one of the three divisions of the treatise; but we shall select 

 the first 100. Within these there are embraced figures and de- 

 scriptions of some 74 species, distributed to about 31 genera. 

 Now this proportion of something like two and a half species to a 

 genus was something new in botany and is therefore one of the very 

 significant features of the book; so much so that we must give it 

 a moment's consideration before passing to a study of the sequence 

 of the genera. In order to reaUze the meaning of my statement that, 

 for the time at which he wrote, the ratio of two and a half species 

 is so great as to amount to an innovation in taxonomy, a brief com- 

 parison must be instituted. The 500 or 600 plants that the ancients 

 had dealt with represented, in the great majority of cases, what we 

 of to-day are accustomed to speak of as monotypic genera. Not 

 any very considerable number of their genera are defined as con- 

 sisting of two or more species; so that they had but one and a sniall 



