122 



diflferent plant, according to time and circumstance, as I explained in a former 

 paper'^ 



PaJeontalogy to wliicli Engler refers in § 10 and §11 is not so very 

 important for the classification of the plants of the present age, as it is thought 

 to be by those who beHeve that the formation of species is only explainable 

 according to the evolution theory. If we think of the innumerable causes^^ of 

 species' coming into existence, such as mutation, crossing, fixation of characters 

 acquired in the course of adaptations, and many others yet unknown to us, 

 we cannot but hesitate to attach importance to paleobotany. 



In § 12, he distinguishes two characteristics of adaptation and of organi- 

 zation, and states that the latter is the quality which should be credited with 

 a superior value in classification. This, in my judgement, will not do. We 

 distinguish tliis as an adaptation - character, and that as an organization- 

 character ; but the demarcation is only for convenience. Not only is there 

 no absohite difference between the two, but on the contrary they are in close 

 inter-relation. For classification, both characters should be taken into con- 

 sideration. This, to be sure, makes the existence of a static system impossible. 

 To this point we shaU return later on. 



Further, he makes reference in § 13'^ to the difficulty of determining the 

 order of the arrangement according to progression and states that the natural 

 system will always be subject to alteration, as it always has been. The 

 former reference is something like an approach to my idea of the impossi- 

 bility of determining the serial orders ; while the latter statement may be 

 taken as partly illustrating my opinion that the natural system can only be 

 brought to realization in its dynamic changeable form. 



What he speaks of in § 14*^ is nearly the same as the statements referred 

 to in § 2, and the remarks which I have made above will do as well for the 

 present case. 



In § 15"^ he refers to the systematic importance of anatomical characters, 



1) Hayata, B. — An Interpretation of Goethe's Blcdt in his " Metamorphose der Pflanzen", 

 as an explanation of the principle of natural classification, in Ic. Pl. Formos. X. pp. 75 — 95. 



2) Wettstein, R. K. — Handbuch der systematischen Botanik p. 49. 



3) Engtjee, A. — 1. c. p. XII. 4) Engleb, A. — 1. c. p. XIH. 

 5) ENGiiKP, A. — 1. c. p. XIIL 



