Text-book of botany, morphological and physiological . also in the leaflet which bearsthe nucule the cells forming the ascending portion of the cortex are also wanting. Asit is the first leaf of the whorl on the stem that produces a branch in its axis, so it isalso from the first (inner) leaflet of the whorl on the leaf that the nucule basal node of the globule in C. fragUis has, according to A. Braun, not four CHARACE.^. 291 peripheral cells, as in sterile leaflets, but five; an upper odd one which is first formed,two lateral ones which follow, and two lower ones which are form
Text-book of botany, morphological and physiological . also in the leaflet which bearsthe nucule the cells forming the ascending portion of the cortex are also wanting. Asit is the first leaf of the whorl on the stem that produces a branch in its axis, so it isalso from the first (inner) leaflet of the whorl on the leaf that the nucule basal node of the globule in C. fragUis has, according to A. Braun, not four CHARACE.^. 291 peripheral cells, as in sterile leaflets, but five; an upper odd one which is first formed,two lateral ones which follow, and two lower ones which are formed last of all. Ofthese five cells only the two lower ones are developed into cells which form the cortex(of the leaves), the upper one, wanting in the sterile basal nodes, is the mother-cell ofthe nucule • but the two lateral ones are developed into leaflets which stand laterallybetween the globule and nucule {cf. Fig. 204, /3); these latter Braun calls mother-cell of the nucule now grows out of the axil of the globule, and divides. FIG. ij^i.—Charafra^ilis; A lower part of a fertile leaf, a lateral bud springing from its axil; B lower part of a sterileleaf without an axillary shoot (in longitudinal section). itself by a septum into an upper outer terminal cell and a segment which in its turn isbroken up into two discs by a w^all paraflel to the previous one (Fig. 210, A, SK). Thelower cell does not divide any further, it forms the concealed pedicel of the nucule,and corresponds to the first internode of a branch ; but the upper one has the characterof a nodal cell; it is divided by tangential walls into a zone of five outer and one innercell (SK) ; the former are the rudiments of the enveloping tubes, which are thereforemorphologically leaves. u 2 :yZ MUSCINE/E. GROUP III. MUSCINEyE. The Hepaticse and Mosses, which are comprised under the term IMuscinese, aredistinguished by a sharply defined Alternation of Generations. From the germinat-ing spore is develo
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
