On the Female Tendencies of the Embryosac-like Giant Pollen Grain of <i>Hyacinthus orientalis</i>

Abstract

1) The relative reduction power and the hydrogen-ion concentration of the embryosac-like giant polten grain in Hyacinthaus orientalis were determined by means of.the indicator method.2) The reduction power of the cytoplasm of the embryosac-like giant pollen grain is larger than that of the normal pollen grain, both in artificially germinated and in non-germinated conditions.3) The reduction power of the cytoplasm of the embryosac-like giant pollen grain decreases after being influenced by the pollen tube.4) The Pollen tubes of another garden variety seldom grow in chemotropism-like manner towards the embryosac-like giant polten grain. In such a Gase, the polten tube usually entwines around the embryosac-like giant Pollen grain and sticks tightly.5) In one Gase, a sperm nucleus was just getting into the embryosac-like giant pollen grain out of the tip of a pollen tube. In another Gase, the P-nucleus was already divided into 16 nuclei, which seems to be caused as the result of a sperm nucleus having already fused with the P-nucleus in the embryosac-like giant pollen grain, though no exact evidence was found.6) From the results of the present investigations, the writer will conclude that the embryosac-like giant pollen grain possesses female tendencies to some degree, not only in general aspects of the development and morphologicaI structure, but also in some of the physico-chemical characters of the cytoplasm and the physiological functions.