Holm — Studies in the Cyperacece. 303 



highly developed, but there is a difference in regard to their 

 mechanical support. Those of the outer band have a large 

 group of stereo me all around the bundle, and especially on the 

 leptome side from where the stereome extends outwards to the 

 epidermis. The mestome-bundles of the innermost band are 

 but a few in number and their mechanical support is very 

 insignificant, there being only a few stereomatic cells on the 

 leptome- and the hadrome-side of these bundles. The third 

 form of mestome-bundles are in regular alternation with those 

 of the outer band ; they are very small, round and are merely 

 supported by a small group of mechanical tissue on the leptome- 

 side, which group is widely separated from the epidermis by 

 the bark-parenchyma. The leptome and hadrome are, how- 

 ever, well differentiated in these small bundles. (Compare 

 figure 3.) 



In considering now the stereome, this forms, as already 

 stated, groups of various strength for the support of the 

 mestome-bundles, and it forms besides an uninterrupted ring 

 inside the two outer bands of mestome-bundles, thus encircling 

 those of the inner band. The innermost part of the stem is 

 occupied by a fundamental tissue, which is composed of large, 

 thin-walled cells, bordering on the rather wide central cavity. 

 Tannin-reservoirs were only observed very scarce in the stem, 

 and they seemed to be confined to the bark, besides that one 

 cell of the hadrome between the two large vessels in all the 

 mestome-bundles was observed to contain this matter. 



The rhizome of our species is well developed, creeping and 

 of a comparatively firm, structure. It contains a huge bark- 

 parenchyma of roundish cells, which forms a circle all around 

 the central-cylinder. Very conspicuous are the numerous 

 tannin-reservoirs, which abound in the bark, increasing in size 

 towards the epidermis. While no typical endodermis is dif- 

 ferentiated, there is, however, a closed ring of stereomatic 

 tissue, just inside the bark, but the cells of this stereome are 

 rather open and with thin walls. It surrounds the entire sys- 

 tem of mestome-bundles irregularly scattered in the funda- 

 mental tissue, and it is, also, represented as supporting groups 

 on both faces of the mestome-bundles, especially on the inner- 

 most face of these. There are two distinct forms of mestome- 

 bundles observable, viz : the ordinary collateral and the so-called 

 concentric, the last of which occur here as perihadromatic ; 

 these two forms do not, however, show any special arrange- 

 ment, but are to be observed scattered among each other. We 

 stated above, that tanuin-reservoirs were abundant in the bark ; 

 they are again to be observed in the fundamental tissue, where 

 they are quite numerous, besides in the stereome and the 



