. Botanisk tidsskrift. Botany; Plants; Plants. - 149 — Sutton (28) and Montgomery (110), who have first more inti- mately investigated this phenomenon. The following division stages correspond with for instance those of Tanacetum or Taraxacum, and the development of the pollen cells does not offer anything extraordinary. The development of the Embryo sac. The reduc- tion process at the development of the ES proceeds altogether in about the same manner as in the case of the PMC. Fig. 9 shows dia- kinesis with distinct- ly different chromo- somes. In fig. 10 a spindle figure is shown with 9 chro
. Botanisk tidsskrift. Botany; Plants; Plants. - 149 — Sutton (28) and Montgomery (110), who have first more inti- mately investigated this phenomenon. The following division stages correspond with for instance those of Tanacetum or Taraxacum, and the development of the pollen cells does not offer anything extraordinary. The development of the Embryo sac. The reduc- tion process at the development of the ES proceeds altogether in about the same manner as in the case of the PMC. Fig. 9 shows dia- kinesis with distinct- ly different chromo- somes. In fig. 10 a spindle figure is shown with 9 chro- mosomes having the same characteristic shapes as in the PMC. Thereupon the second division takes place and the construction of the tetrad. The lower of these cells be- comes the ES. The further de- velopment of the ES takes place in the ordinary way. I have, it is true, not yet succeeded in fin- ding out the fusion of the male and fe- male nuclei, but a calculation of the number of the chromosomes in the eggcell and in the first divisions of the endosperm nuclei shows without doubt that a double fertilization takes place. In the endosperm the nuclei divisions occur at least at the beginning very regularly. Very often I have been able to determine their number at 27, that is to say 9 + 9 + 9. The endosperm nucleus has 18 chromosomes, as it is formed by the fusion of two polar nuclei, each one with 9 H. venosum, A - E, heterotypic spindle figures, in E a polar view; F, Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Botaniske forening i København. København : H. Hagerups Forlag
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Keywords: ., bookcentury1800, bookdecade, booksubjectbotany, booksubjectplants
