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SCIENCE 



[N. S. Vol. XLIII. No. IIOS 



is seeking differences, for the resemblances 

 are plain to be seen. 



Intermediate between the species and the 

 family lie groups, such as the genus and the 

 tribe, in which one must look for both differ- 

 ences and resemblances and strike a bal- 

 ance between them. The botanist who 

 studies species, and hence looks for differ- 

 ences, compares the more superficial char- 

 acters of plants, those that are most easily 

 modified in the development of new forms. 

 The botanist who studies the relation of 

 orders and more comprehensive groups, is 

 concerned chiefly with those characters 

 which have resisted modification in the 

 icourse of development. I have referred to 

 4he work of the former as descriptive tax- 

 onomy. The work of the latter is often in- 

 cluded in the designation comparative 

 morphology. It is to be regretted that there 

 has been some lack of understanding be- 

 tween these two groups and a consequent 

 lack of sympathy. A title such as "The 

 Morphology of Cycas and Welwitschia and 

 its Bearing on the Origin of the Gymno- 

 sperms" would attract one group as being 

 an important paper in comparative mor- 

 phology, while a title such as "Five Hun- 

 dred New Species of Ruhus" would be 

 laid aside with the remark, "another spe- 

 cies-maker broken loose." The one looks 

 upon the other as a species-maker who 

 knows little of the real problems of botany. 

 The other looks upon the one as a section- 

 cutter who knows plants only through the 

 compound microscope. Both may be doing 

 really good taxonomie work. This is deter- 

 mined, however, not by the fact that one is 

 cutting sections and the other is describing 

 species, but by the fact that each is using 

 scientific methods and is dominated by the 

 scientific spirit. 



The ideal of the taxonomist is a scheme 

 which shall represent the genetic relations 

 of organisms. Each of us who are taxon- 



omists is hoping to contribute his mite to- 

 ward this harmonious whole. The lines of 

 descent are real though unseen ; they exist, 

 but their position and direction can not be 

 proved. As the astronomer studies the con- 

 stitution and evolution of the universe, as 

 the chemist studies the constitution and evo- 

 lution of matter, so the taxonomist studies 

 the constitution and evolution of organisms. 

 One of us may be describing new species 

 of Ruhus, and showing their relation to 

 previously known species. Another may be 

 revising a genus of mosses and adjusting 

 the relations of the species in the light of 

 recently acquired knowledge. Another may 

 be studying the comparative anatomy of 

 seaweeds and with the observed facts at- 

 tempting to solve the problem of relation- 

 ship. Another may be studying the devel- 

 opment of the spores of smuts and tracing, 

 as it were, the prehistoric development of 

 the group. Thus are anatomy, morphology, 

 ontogeny, paleontology, yielding facts to 

 taxonomy. Thus are we all uniting in the 

 great effort to answer the fundamental 

 question, how are plants related. 



Considering the trend of botanical 

 thought during the present decade, I need 

 not ask the members of this society if com- 

 parative morphology is an interesting field 

 of research. My predecessor and my suc- 

 cessor are shining examples of those who 

 have advanced the limits of our knowledge 

 in this branch. But the domain of descrip- 

 tive taxonomy, the elaboration of genera 

 and species, is this an inviting field for the 

 young botanist who is seeking an oppor- 

 tunity to take part in solving the problem of 

 relationships ? 



For reasons already given this branch has 

 been unpopular in recent years. Though 

 descriptive taxonomy will never attract 

 workers to the proportionate extent that it 

 did before the rise of the experimental sci- 

 ences, yet it will be found to satisfy the 



