1. Internally it shows four chambers called microsporangia or pollen sacs.
2. The anther consists of two main parts, viz., anther wall and microsporangium or pollen sac.
3. The wall of the anther can be differentiated into four layers, viz., epidermis, endothecium, middle layers and tapetum.
4. The epidermis is the outermost layer of the anther wall. It is made up of flattened cells which are protective in function.
5. The endothecium lies internal to the epidermis. It is made up of a single layer of cells. The cells of endothecium show fibrous thickenings on radial walls.
6. Internal to the endothecium, lie 1 to 3 layers of parenchymatous cells forming middle layers of the anther wall. The cells of middle layers degenerate at maturity during the formation of microspores.
7. The tapetum is the innermost nutritive layer of the wall of the anther, consisting of a single layer of cell surrounding the sporogenous tissue.
