Text-book of botany, morphological and physiological . shall investigate at the proper time (Book ). b. The contracting daughter-cells secrete cel-lulose enjen during their reparation. Sincein this case the mother - cell is alreadyclothed with cellulose, the process oftengives the impression that the cell-wall ofthe mother-cell forms at certain spots aprojecting ridge on the inside, constrictsthe protoplasmic body, and at length se-vers it. The clearest examples of this case occurin the formation of the pollen of many Dico-tyledons. Fig. 11 shows this process in Iro-pcEolum fnin
Text-book of botany, morphological and physiological . shall investigate at the proper time (Book ). b. The contracting daughter-cells secrete cel-lulose enjen during their reparation. Sincein this case the mother - cell is alreadyclothed with cellulose, the process oftengives the impression that the cell-wall ofthe mother-cell forms at certain spots aprojecting ridge on the inside, constrictsthe protoplasmic body, and at length se-vers it. The clearest examples of this case occurin the formation of the pollen of many Dico-tyledons. Fig. 11 shows this process in Iro-pcEolum fninus. At a and b four nuclei havealready appeared in the protoplasm of themother-cells which are much thicker on twosides, arranged at the angles of a tetrahedron(this arrangement is common, though notwithout exception); the protoplasm gives,in fresh examples, the impression of beingalready divided into four roundish lumps; but by contraction in an alcoholic solutionof iodine (/, g, h, k) it is seen that they are still connected, and that the cell-wall. Fig. 10.—Mode of formation of the spores of Egnisetmnhmosutn (XS50); a group of four, b group of two uiother-cells; c and d mother-cells preparing for division ; e one withtwo nuclei ;y;^ and i division into four spores ; h abnormalfonnation of three spores from one mother-cell.
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
