. Dansk botanisk arkiv. Plants; Plants -- Denmark. 272 Dansk Botanisk Arkiv, Bd. 3. Nr. 1. The plant forms small low tufts about 1—l'/g cm high; it was found near the surface of the sea, where is was constantly- washed by the waves. It has four pericentral cells (Fig. 267 6). The base consists of creeping decumbent filaments fastened to the substratum by means of rhizoids breaking out from the lowermost cells in the fila- ment, sometimes two from the same cell (Fig. 267 a). The thicker basal cells are about 150^«, sometimes up to 200/^ thick and the length of the cells about 125//; but these f
. Dansk botanisk arkiv. Plants; Plants -- Denmark. 272 Dansk Botanisk Arkiv, Bd. 3. Nr. 1. The plant forms small low tufts about 1—l'/g cm high; it was found near the surface of the sea, where is was constantly- washed by the waves. It has four pericentral cells (Fig. 267 6). The base consists of creeping decumbent filaments fastened to the substratum by means of rhizoids breaking out from the lowermost cells in the fila- ment, sometimes two from the same cell (Fig. 267 a). The thicker basal cells are about 150^«, sometimes up to 200/^ thick and the length of the cells about 125//; but these filaments are often much thinner, some- times not more than 60 //, and the length of the cells about 100 u. The creeping filaments bend upwards in their upper end, forming in this way an even transition to the erect filaments (comp, flg. 267 a). The latter, too, are often provided with hap- ters which fix themselves to neighbouring filaments, ser- ving in this way to keep the tuft Fig. 267. Polysiphonia sphserospora nov. spec, a, Base of a filament with rhizoids. b. transverse section of a filament. (a, about 50:1, b, 130:1). The erect filaments, whether they issue from the creeping fila- ments or are the upwardbent summits of these, taper evenly towards their summit. In the basal part they are about 100// thick and the cells about 150// long; near the summit the filaments are mostly only half as broad as at their base. In the thinner fila- ments the cells are sometimes three times as long as the diameter of the filament; f. i. a filament was about 60 fx thick and the cells about llbu long. While in the older parts of the thallus the filaments are al- most cylindrical, the segments in the young parts are often sub- sphærical or barrelshaped, and the filaments in this way get a moniliform appearance (Fig. 268). The branches issue without any connection with the trich- oblasts (Fig. 269). The latter are developed upon each seg-. Please note that these images are ext
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