Abstract
1) The embryosac-like giant pollen grain is produced in the anthers of the Hyacinth bulbs subjected to high temperature at about the stage when the reduction division of the pollen mother cells is going on, and further forced in the green house.
2) It was experimentally proved that the formation of such embryosac-like giant Pollen grains is closely linked with the stage of the Pollen development, accompaniment of the abundant dead pollen grains and suitable temperature. If one of these three factors is omitted, no such an embryosac-like giant pollen grain is produced.
3) It may be assumed that the “Necrohormone” in HABERLANDT'S meaning may act to form such embryosac-like giant pollen grains, if suitable temperature is applied.
4) From the result of the present work the writer can not agree with the opinion of DE MOL, that the triploid Hyacinthus-plant is produced by pollination with the “diploid” pollen grain produced by so-called “physiological stimuli” of his meaning.
