93 



demands that such a natural system be a static one^^ like Bentham- Hooker's 

 or Engler's, and that there is possible only one true ideal system, to which, 

 however, we are as yet far from attaining, as but one phylogenetic tree is 

 possible^\ Much against my will, I have come to entertain strong doubts as 

 to the effectiveness of the modern systematizers' effort to attain to the ideal 

 system ; and my twenty year's experience in systematic botany has steadily 

 led me into quite a different channel of thought. Tliis I now venture to make 

 public, though I am aware that it will meet with a great deal of opposition. 

 All systematizers regard the natural system as a static one with a definite 

 form and believe that all species, genera or families have their fixed natural 

 positions, so as to be arranged between this and that, according to their 

 natural relations. My idea is quite different *from this current opinion, I 

 r^ard the natural system as a dynamic one, changing with the view of the 

 systematizer and subject to alteration, according to the way in which it is 

 considered, and I believe that none of the species, genera or families has a 

 fixed natural position, but has changeable positions, subject to alteration 

 according to the criterion for comparison. It is neither natm'al nor necessary 

 that a species should in aU cases be arranged between this limit and that ; 

 but should be placed between this and that according to one view, or between 

 another this and another that according to another view. In the present paper. 



1) Among the literatiue which treats of the principle of natural classification, I may men- 

 tion the following works : — 



Dabwin, C. — On the Origin of Species, (New York, 1890) ; Divei^ence of Character, and The 

 Probable Effects of the Action of Natnral Selection throiigh Divergence of Character antl Extinc- 

 tion, on the Descentlants of a Common Ancestor, 1. c. pp. 86-97 ; Classification, 1. c. pp. 363-381. 



Haeckel, E. — Prinzipien der Generellen Morphologie der Organismen (Berlin 1906) ; Das 

 natiirliche System als Stammbaiim (Prinzipien der Klassifikation), 1. c. p. 390. 



Englee, A. — Erlaiiterungen zu der Ubersicht iiber die Embroyophyta Siphonogama, in den 

 Natiirhchen Pflanzenfamilien, Nachtragen zum II.-IV. Teil, (1897), pp. 358-380. 



, — . — Prinzipien der Systematischen Anordnmig, im SyUabvis der Pflanzenfanulien, 



siebente Auflage, Berhn, 1912. 



Haluek. H. — Provisional Scheme of the Natural (Phylogenetic) System of Flowering Plants, 

 in the New Phytologist, Vol. IV., No. 7, (July, 1905), pp. 151-162. 



, — . — Ein Zweiter Entwurf des natiirhchen (phylogenetischen) Systems der Bltiten- 



pflanzen, in den Berichte der Deutsshen Bot. Gesellsch. XXIII., 2, pp. 85-91. 



LoTSY, J. P. — VortrSge iiber Botanische Stammesgeschichte, I., Jena, (1907). 



Wettstkin, R. — Handbnch der systematischen Botanik (Zweite Auflage, 1911) ; Allgemeiner 

 Teil, L c. pp. 1-49. 



2) Hallibb, H. — Provisional Scheme of the Natural System, 1. c. p. 152. 



