THE AMERICAN BOTANIST. 95 



Six well known botanists gave the leading papers, Dr. Charles 

 E. Bessey and Dr. N. L. Britton speaking on the taxonomic 

 aspect, Dr. J. C. Arthur and Dr. D. T. MacDougal on the 

 physiological aspect, and Dr. Frederick E. Clements and Dr. 

 H. C. Cowles on the ecologic aspect. The eminence of the 

 speakers in their respective fields and the care with which 

 the papers had evidently been prepared, gave unusual weight 

 to the opinions expressed. Contrary to what might ordinarily 

 be expected from men who look at the question from such 

 widely differing viewpoints, there was remarkable unanimity 

 in the conclusions drawn. The work of De Vries and others 

 in recent years has made it impossible to ignore a host of 

 forms less than species in the ordinary sense, and the pres- 

 ence of these for a time bid fair to still further complicate 

 the species question, but fortunately for science they are now 

 being regarded as additional aids toward defining a species. 

 Dr. Bessey fairly expressed the sentiment of the symposium 

 in his statement that nature produces individuals and not 

 species, and that a species is a mental concept and nothing 

 more. The excuse for the species concept at all is that it saves 

 labor by allowing us to think in terms of the group rather than 

 in terms of the individual. Excessive multiplication of spe- 

 cies, therefore, is to be deplored as a great number of species 

 defeat the very end for which the species concept was origina- 

 ted. Dr. Bessey holds that all plants should be included in as 

 small a number of species as possible, and that species-makers 

 should look for resemblances in plants instead of differences. 

 Descriptions of species should be brief enough to be easily 

 remembered, and a species that cannot be identified by its 

 diagnosis or description has no right to exist. Dr. Britton 

 made a surprisingly conservative address detailing early con- 

 ceptions of species, recognizing the lesser forms of today and 

 suggesting that the latter be treated as elementary species, 

 races, forms, varieties, sub-species, or possibly numbered vari- 



