Cytoplasmic Nodules in the Endosperm of some Cucurbitaceae

Abstract

CYTOPLASMIC extensions of definite shape growing into the embryo sac during endosperm development have been termed cytoplasmic nodules or vesicles. They are of two types, nucleated and non-nucleated. Nucleated nodules are reported in Impatiens roylei ¹, Isomeris arborea ² and Musa errans ³, while non-nucleated nodules occur in Oldenlandia corymbosa ⁴, Pennisetum typhoideum ⁵ and Stackhousia linariae-folia ⁶. Billings ² has reported the development of the embryo from the nucleated nodules in Isomeris arborea. Maheshwari and Sachar (unpublished work) have, however, contradicted this and find that the embryo arises from the egg as in other angiosperms. Farooq⁴ has reported in Oldenlandia corymbosa that these nodules become detached from the general cytoplasm and ultimately degenerate, but I do not agree with him (see below).