135 



understand the natural relations between tlie different series of the Dicotyledones, 



each of the latter should be viewed in every possibly diiferent light, and divided 



and grouped according to every possible means. This is what I intend to 



show in my dynamic system. 



As to the criteria for classifying the Archiclamydea3, Engler says as 



follows :^^ — 



Fiir clie Anordnung der Keihen irmerhalb der Archichlamydeoe sind vorzugsweise 

 die Axisbildung der Bliitenbiillen, der Bliitenacbse und die Anordnung der Bliiten- 

 pbyllome maSgebend ; 



In a word, his system is one that shows here a parfcial relation between 



family A and family B ; and thero another parfcial relation befcween family B 



aud family D, mosfcly according to the ciiterion of fiowers. Now, we shall 



look at the matfcer series by series. 



Beginning with the Verfcicillat£8, Engler plaoes the series'^^ at the com- 

 mencement of the Dicotyledones. It is closely allied to the Gnetales, as can be 

 seen in the agreement in the course of the vascular bundles in Epliedra and 

 CasuarinoP, The resemblance is still greater in the structure of stomata and 

 in the development of embryo. On the other hand, if chalazogamy which is 

 found in the Casuarinacese, Juglandacese, Betulaceae and cerfcain Urfcicacese^^ is 

 taken into consideration, the Verfcicillatae seem to have some aUiance with the 

 Juglandales and Fagales. Eurfchermore, the Verticillatse seem to beiix some 

 resemblance to the Eagales and in all probabihty to the Ericacese'^^ Its 

 natural position, therefore, is not a settled one, but should be a dynamic one. 



As to the Piperales, our knowledge is not yet sufficient to decide the 

 relations between this series and others. 



Next, Engler places the Salicales'^^ between the Piperales and the 

 Garryales; but the view is, as far as my knowledge exfcends, entirely one- 

 sided. A close relation of this series and the Parietales is not to be 

 disputed, when we see, on comparing the Sahcacese''^ and Tamaricacese, their 



1) Englek, A. — Erlauterungen, 1. c. p. 362. 



2) ExGLEH, A. — Erliiutemngen, 1. c. p. 3 2. 



3) Nat. Pfl.-fara. ni.— 1, p. 18, and Kacht. III. p. 92. 



4) Jeffrey E. C. — The Anatomy of Woody Plants, (Chicago, 1917) p. 376. 



5) Jeffrey, E. C. — 1. c. p. 38o. 6) Engleb, A. — ErlRuterungen, 1. c. p. 362, 

 7) Nat. Pfl.-fam. ni.— 1, p. 35. 



