The Movements of the Stamens of Portulaca grandiflora (IV)

Abstract

Studies were made of the cross and vertical sections of Portulaca filament.
Portulaca filament is made from 3 parts, namely epidermis, parenchyma and vascular bundle. Epidermis is a layer of large cells (dimentions-10×30×100μ³) arranged side by side. In the parenchyma there are many intercellular spaces which have gaseous substances. Vascular bundle consists of xylem and pholoem.
The stracture of the Portulaca olelacea filament is almost similar to that of the Portulaca grandiflora.
When the freezing preparation is defrozen, it is observed that the membrane of epidermal cells bends inward at a papilla. The author thinks that the membrane of epidermal cells has a tendency to contract such like and this contractibility of the membrane has some kind of relation to the movement of Portulaca stamen.