362 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



While this specialization is doubtless justifiable up to a certain point, 

 the time will soon come when these physiological-ecological inves- 

 tigations must be supplemented by and brought into relation with 

 phylogenetic considerations. When this stage is fully reached it 

 is manifest that the knowledge of every type available will be a 

 matter of vital concern, and even forms of no great floristic interest 

 may prove to be of large historical value. To illustrate, I possess 

 as a loan a single incomplete specimen of a Laciniaria from Illinois, 

 with characters rare in that region and so related to species there 

 and elsewhere as to throw a strong ray of light on the history of a 

 group. It is very possible that this species will never be collected 

 again. Recently, however, (in my 1909 collection) a single specimen 

 of a related species has come to light. Not all forms, of course, 

 have as much significance, but we can not afford to lose any of them. 

 Taxonomy, if we mean thereby merely an arrangement for con- 

 venient reference, is of course merely ancillary; but if it means 

 the orderly expression of phylogenetic relations it ceases to be a 

 mere tool and becomes the embodiment of some of the highest 

 aspirations of botanical science. 



But even from an ecological point of view it can easily be shown 

 that the study of this flora is urgent. The Illinois flora, ecologically 

 considered, is intermediate in type between that of the wooded 

 country and that of the subarid region farther west, and only by a 

 careful attention to species can the different areas be accurately 

 marked out. My own Laciniaria studies have shown that of a 

 swarm of species of the scariosa type naturally inhabiting Illinois 

 and Wisconsin not a single one reaches the western boundaries of 

 Missouri and Iowa, while only a few are known to cross the Mis- 

 sissippi at all, though it is probable that a considerable number do. 

 In like manner there is an almost if not quite complete replacement 

 of species in passing from northern Illinois to southern Minnesota. 

 I put it to the ecologists themselves whether any accurate phytoge- 

 ographical results can be obtained where a hundred types are bulked 

 in one. 



What is needed is a systematic and thorough survey conducted 

 by qualified persons. While the work of the stronger amateurs 

 has been of immense value and while the efforts of amateurs whether 

 stronger or weaker are to be earnestly encouraged, yet it is plain 

 that these volunteer performances are insufficient. For one thing 

 they are sporadic and fragmentary. But besides this only experts 

 can make the requisite discriminations. Even collectors of expe- 

 rience often fail to recognize the new species in their own collections, 

 particularly outside of a certain range within which their individual 

 interest has been peculiarly awakened. They also pass by plants 

 which are really of new species because they are confounded with 

 species already collected. 



