Wet Epiphragm loose, teeth not stretched, gaps between teeth disappear. Dry Epiphragm taut, teeth stretched, gaps develop between teeth, allowing spores to sift out. Tortula Peristome teeth long and hair-like. Wet Teeth elongate and are tightly wrapped around each other. Dry Teeth shrink, disentangling, allowing spores to sift out.
Dead plants provide peat moss.
Capsule contains air and spores. The operculum is shot off and spores with it. This actually makes a popping noise. The peristome forms a fringe at the top of the capsule. The columella sticks out of the top, covered in sticky spores.