Calyptra is a small sheath of cells, derivedfrom the archegonia, which covers top of the capsule. Capsule is a sporophytic region of mosses. Antheridia is a small structure that produces sperms in bryophytes or pteridoyphytes. In fungi the young sporangium is a white spherical structure situated at the free end of the sporangiophore. At maturity it turnsblack. The black colour is due to the presence of sooty spores. The centre of the sporangium is a large dome-shaped structure called the columella.