The ovule is bitegminous and tenuinucellate.The archesporial cell locates under the nucellus epidermis, which develops into fuctional megasporocyte.

原细位于皮之下，直接起大子母细的功能。

Tapetum (pl. tapeta) A food-rich layer surrounding the spore mother cells in the anthers of vascular plants.

维管植物花粉囊内子母细的富含营养物质的一层结构。