After Aristotle 55 



and mode of life of living things on the basis of the Evolu- 

 tionary philosophy. Nearly all the work on morphology and 

 much of that on physiology since his time might be treated 

 as a commentary on the works of Darwin. These volumes of 

 Theophrastus give the same impression. They represent the 

 remains alas, almost the only biological remains of a school 

 working under the impulse of a great idea and spurred by the 

 memory of a great teacher. As such they afford a parallel to 

 much scientific work of our own day, produced by men without 

 genius save that provided by a vision and a hope and an ideal. 

 Of such men it is impossible to write as of Aristotle. Their 

 lives are summed up by their actual achievement, and since 

 Theophrastus is an orderly writer whose works have descended 

 to us in good state, he is a very suitable instance of the actual 

 standard of achievement of ancient biology. ' Without vision 

 the people perish ' and the very breath of life of science is 

 drawn, and can only be drawn, from that very small band of 

 prophets who from time to time, during the ages, have pro- 

 vided the great generalizations and the great ideals. In this 

 light let us examine the work of Theophrastus. 



In the absence of any adequate system of classification, 

 almost all botany until the seventeenth century consisted 

 mainly of descriptions of species. To describe accurately a leaf 

 or a root in the language in ordinary use would often take 

 pages. Modern botanists have invented an elaborate termino- 

 logy which, however hideous to eye and ear, has the crowning 

 merit of helping to abbreviate scientific literature. Botanical 

 writers previous to the seventeenth century were substantially 

 without this special mode of expression. It is partly to this 

 lack that we owe the persistent attempts throughout the 

 centuries to represent plants pictorially in herbals, manuscript 

 and printed, and thus the possibility of an adequate history 

 of plant illustration. 



Theophrastus seems to have felt acutely the need of botanical 



