Sporangia are produced along the lower margin of the leaves of Pteris. The sporangia together form a brown kidney-shaped sorus. The upper part of sporangium is called capsule. Inside the capsule are sporogenous cells. 16 spore mother cells are produced from sporogenous cells. In the process of meiosis, 64 spores are produced from 16 spore mother cells. The resulting spores are dark brown in color and have the same characteristics. It is double-layered and equipped with germpores. After spore formation, the water holding capacity of the sporangium decreases and becomes dry. This causes tension on the annulus and ruptures the stoma transversely. As a result, the spores are released. Spores germinate to form new gametophyte plants.
