. Dansk botanisk arkiv. Plants; Plants -- Denmark. 288 Dansk Botanisk Arkiv. Bd. 3. Nr. 1. of rhizoids break out (comp. fig. 287). They issue from the fore- most end of each cell. These rhizoids are often of considerable length, up to 1mm or more, but seldom ramified. They have no walls and do not generally end in a disc. Only a few have been found with a rather irregular disc, like those described by Am- BRONN, 1. c, p. 211. From the mother-cell the rhizoids are separated by an oblique wall. The cylindrical stem of the rhizoids is about 30 jx thick. Upon the dorsal side, the main stem bears t
. Dansk botanisk arkiv. Plants; Plants -- Denmark. 288 Dansk Botanisk Arkiv. Bd. 3. Nr. 1. of rhizoids break out (comp. fig. 287). They issue from the fore- most end of each cell. These rhizoids are often of considerable length, up to 1mm or more, but seldom ramified. They have no walls and do not generally end in a disc. Only a few have been found with a rather irregular disc, like those described by Am- BRONN, 1. c, p. 211. From the mother-cell the rhizoids are separated by an oblique wall. The cylindrical stem of the rhizoids is about 30 jx thick. Upon the dorsal side, the main stem bears two kinds of branches, some with in- definite growth able to grow out to a main filament like the mother stem, and some with limited growth. In the following we may call them respectively branches and branch- lets. The branches with continuous growth are placed alternately on both sides of the main stem, one upon each segment, and in such a way that there in the typical form are always three segments between those bearing the branches (Fig. 287). Upon the upper dorsal side of these three segments the branchlets with definite growth issue. These are placed singly, that is, a single one upon each segment, in two rows and in such a way that after each branch with continuous growth a branchlet is de- veloped from the opposite side of the stem; if this branch is found on the left side of the stem, the following branchlet is placed on its right side, the next one is then found on the left side and the third again to the right, then follows a branch on the right side and so on. Ambronn, 1. c, pi. IV, fig. 17 and Falkenberg, 1. c, p. 303 have given clear diagrams of the arrangement of the branches and branchlets. At first the branchlets are much more developed than the young branches. The young branchlets are much curved in the opposite direction to that of the summit of the main stem, bending down over the latter as a protecting cover (comp. fig. 287). The branchlets are never ramified
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