Mabch 10, 1916] 



SCIENCE 



333 



from exploring expeditions yielded scores 

 or even hundreds of new species. Is it to 

 be wondered at that taxonomy held a domi- 

 nating position in botanical research and 

 that most of the great botanists of the 

 period were taxonomists? At the begin- 

 ning of this period modern chemistry and 

 physics were in their infancy and the com- 

 pound microscope had not yet been per- 

 fected. It is easy to see why it was that 

 well along into the nineteenth century bot- 

 any was considered to be chiefly the de- 

 scription and classification of species. 

 Furthermore, botanists were working upon 

 the hypothesis of created species, not upon 

 that of the evolution of species. 



Let us turn back for a moment to note 

 the growth of experimental science. Of 

 science as we understand it there was little 

 in the middle ages. Instead was authority. 

 Arguments were settled, not by direct test, 

 but by consulting the statements of the 

 Fathers. Tradition hampered the develop- 

 ment of all branches of human research, 

 especially of the sciences. The statements 

 of Aristotle were for ages considered in- 

 fallible. That the root of the mandrake 

 cried with pain when torn from the earth 

 and that the fruit of the goose tree devel- 

 oped into bird or fish according as it fell 

 upon the land or in the water, was ac- 

 cepted without question. Here and there 

 a courageous soul by questioning tradition 

 created much disturbance and brought 

 upon himself the revilings or at least the 

 reproaches of the powerful. Slowly at 

 first, more rapidly during the latter part 

 of the eighteenth century, grew the tend- 

 ency to test theories by experiment, to 

 verify facts. Great minds were attracted 

 to the field of scientific research. There 

 was a certainty about the relation between 

 cause and effect that was vastly satisfying 

 to the intellectually alert. The discovery 

 of oxygen by Priestly in 1774 gave an im- 



petus to chemistry. Upon the foundation 

 of facts accumulated up to about the time 

 that Davy decomposed potash in 1808, 

 Dalton was able to present a theory of the 

 construction of matter, the atomic theory, 

 which to a remarkable degree has answered 

 up to the present time the requirements of 

 a working hypothesis even though modi- 

 fied by recent discoveries. Faraday, the 

 great experimenter, somewhat later laid 

 the foundation for the extraordinary de- 

 velopment in the domain of electro-mag- 

 netics. The microscope was greatly im- 

 proved, opening up a wide field of research 

 concerning the internal structure of plants. 

 During the nineteenth century there was 

 much interest in plant anatomy, in the de- 

 velopment of the cryptogams, and finally 

 in plant physiology. A growing propor- 

 tion of botanists devoted their attention to 

 these or allied branches. The theory of 

 the special creation of species was super- 

 seded by that of the evolution of species. 

 As the experimental method was widened 

 in its application to the various fields of 

 botanical research, the science of botany 

 became increasingly attractive to intellec- 

 tual workers. But in this increased inter- 

 est and activity descriptive taxonomy has 

 not retained its share. At the beginning 

 of the nineteenth century nine tenths of 

 the prominent botanists were engaged in 

 the discrimination of species. At the be- 

 ginning of the twentieth century probably 

 not one tenth are thus engaged. This re- 

 versal of proportion is due in part to the 

 widening field of botany. Still I think 

 that there is at present in descriptive 

 taxonomy an evident lack of interest that 

 is not entirely explained by this widening 

 of the field of botanical research. 



What are the reasons for this lack of in- 

 terest in what is conventionally known as 

 systematic botany? Some botanists, espe- 

 cially of the younger generation, have be- 



