Light micrograph of the leaf of the bog moss, Sphagnum recurvum. A continuous network of true cells (elongated) surrounds numerous, partitioned chambers. The elongated true cells contain chloroplasts (small green bodies), the sites of photosynthesis within the cell. The partitioned chambers retain water and give the plant its sponge- like properties. All species of Sphagnum grow in moist places such as bogs and ponds; dead bog moss forms peat. Because of its water holding capacity, Sphagnum is used as a packing material for the transportation of cultivated plants.