Because they don't have roots and stems to transport water, mosses dry out very quickly, so they are usually found in moist habitats. The only place they don't grow is in salt water. Moss plants are usually very small. They have leaf-like structures or phyllids that are usually only a single cell layer thick. The phyllids spiral around a stem-like structure called the caulid .
Mosses reproduce in an unusual way.
There is a first generation moss, the gametophyte . The gametophyte produces a sperm and an egg. They come together and grow into the next generation, the sporophyte . The sporophyte usually grows on a stalk or seta . The sporophyte has no chlorophyl and lives on a gametophyte.