Endothecium

Endothecium is a type of tissue found in the walls of anthers and in moss capsules. This tissue is usually one to several layers thick, and is composed of cells that have walls of uneven thickness. In anthers, the endothecium is responsible for the tensions that lead to anther dehiscence, or splitting. It is the uneven thickness of the cells walls that cause this. The cells lose water, and the uneven thickness causes the thinner walls of the cells to stretch to a greater extent. This creates a tension that eventually leads to the anther being split along its line of weakness and releasing pollen grains to the atmosphere.