Morphological Studies of the Nymphaeaceae. X. The Seed of Ondinea purpurea Den Hartog

Abstract
The mature seed anatomy and morphology of O. purpurea den Hartog (Nymphaeaceae) was studied. The seeds are arillate and perispermous. The outermost cell layer of the testa is composed of interlocking, puzzle-shaped sclereids. Each cell of the perisperm contains several packets of starch granules. Endosperm is cellular and consists of a single or double layer surrounding a minute embryo. An operculum and hypostase are present. The embryo bears 2 large, separate cotyledons. Den Hartog''s hypothesis that Ondinea is closely related to Nymphaea is supported. The presence of 2 cotyledons is discussed in relation to the presumed monocotyledonous nature of the family.