Embryo sac formation in  Polygonum and most common type of endosperm development

Embryo sac formation in  Polygonum and most common type of endosperm development  both involve free nuclear mitosis. The most common type of endosperm formation is free nuclear endosperm. During this endosperm development  , the PEN undergoes successive nuclear divisions to give rise to free nuclei. During embryo sac formation the mitotic divisions are strictly free nuclear.