The embryo-sac of Euphorbia heterophylla L.- a reinvestigation

Abstract

A reinvestigation of the embryo-sac of Euphorbia heterophylla shows that the development is not of the Adoxa- type as reported by Sanchez (1938) but of the Normal- type. The megaspore-mother cell gives rise to a tetrad of megaspores of which the chalazal cell functions to produce a normal 8-nucleate embryo-sac. It is pointed out that as a rule vacuolation and polarity are not seen in embryo-sacs until after the reduction divisions are over. They form such reliable guides that all cases, where the reported observations are not in accordance with the above, deserve a fresh study.