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loured red immediately when treated with phloroglucine and hydro- 

 chloric acid. By many species two ridge-formed longitudinal stripes 

 are to be found on the outside of the outer-walls of every cell 

 (fig. 4, C, D) ; by some few species a great many very fine stripes, 

 besides the two stronger ones, are to be found. This sculpture on 

 the outer walls of the epidermis-cells, however, is hardly at any 

 greater extent an employable character because by the same species 

 it is not always distinctly present. This question, however, needs 

 a closer examination. 



The bark is always very lacuneous with one or more circles 

 of lacunae (figg. ï, C; 8; 9), the separating walls of which generally 

 consist of but one stratum of cells except in the corners, where more 

 walls meet, here the walls are often thicker especially when vascular- 

 bundles or bast bundles are to be found in the bark. The lacunae 

 are lying in ranges lengthwise through the stem. The cross- walls 

 separating the lacunae of the same longitudinal range appear in 

 greater or smaller distance of each other and vertically on the 

 longitudinal axis of the stem. The cross-walls consist but of one 

 stratum with larger or smaller intercellular-spaces. The number of 

 lacunae-circles are often very different by different species and in 

 several cases employable by the separation of species. Towards the 

 axial cylinder the lacunae grow quite small and become common 

 intercellular-spaces. By the making out of the number of lacunae- 

 circles these quite small spaces must not be reckoned. In the 

 species that have a very compressed stem, there are more lacunae 

 in the long diameter than in the short one (Fig. 1 C). 



A good many species have vascular- or bast-bundles in the 

 bark, while others are without such bundles; this fact is of a great 

 systematical importance. As before said these bundles are lying 

 where the walls between the lacunae meet. The richest endowed 

 species have several circles of bundles spread in equal proportion 

 throughout the bark, the outside circle being where the radial walls 

 between the outer lacunae adjoin the epidermis (Fig. 8). The inner- 

 most bundles are, as a rule, rudimentary vascular-bundles sur- 

 rounded with bast (Fig. 2 E) ; towards the circuit of the stem the 

 vascular-part of the bundles most often disappears entirely and 

 only the bast remains. As far as I can see the type with the 

 richest endowment of bundles is the most primary one from which 

 the other types must be derived. In some species the bundles in 

 the bark are reduced to a circle of subepidermal bast-bundles 



