Mosses and liverworts don't produce flowers. Instead they have a complicated life-cycle with two stages. The green, leafy bit is called the gametophyte, and the reproductive bit is called the sporophyte. It's a capsule on a little stalk. This is bank haircap.
📷️ Jenny Tweedie
ALT A strange looking papery type shape on a long stalk with green fronds of moss behind