- 142 — 



which several are of special interest for the present question, 

 and I can on the whole support the descriptions by the earlier 

 investigators. Of the Fagales — and it is from amongst these 

 that the American botanists have got their most important proofs 

 — I have investigated Fagus silvatica (Fig. 1), Quercus peduncu- 

 lata, Alnus glutinosa (Fig. 2), A. incana and Betula sp. All these 

 species present distinctly separate bundles in the youngest parts of 

 the stem. In his paper: "Recherches sur la naissance des feuilles 

 et sur l'origine foliaire de la tige (Revue gén. de Bot., 19, 1907), 



Fig. 1. Fagus silvatica: Transverse Fig. 2. Alnus glutinosa: Transverse 



section of a part of the central section of a part of the central 



cylinder; young vascular bundle; cylinder; young vascular bundle; 

 X c. 450. X c. 550. 



L. Flot gives a very instructive figure of the young stem of a 

 Betula. Here is shown not a solid cylinder, but distinctly separate 

 bundles. 



Also in Fraxinus excelsior, Sorbus aucuparia and Euonymus 

 latifolia (Fig. 3) I have found young bundles. Amongst herba- 

 ceous plants and shrubs I have examined Linum austriacum (Fig. 4), 

 Potentilla palustris, Rubus Idseus (Fig. 5) and Rubus sp., Hype- 

 ricum quadrangulum (Fig. 6) and some Veronica species. Of 

 these species, of which Linum, Hypericum, Potentilla, and Veronica 

 possess an early developed continuous cylinder, I have proved the 

 existence of isolated bundles besides distinct leaf-trace bundles. 

 In Hypericum, Potentilla palustris as well as in Veronica, it is 



