In Characeae no fewer than four methods of vegetative reproduction have been described, and the facility with which buds and branches are in these cases detached has been adduced as an evidence of affinity with Bryophyta, which, as a class, are distinguished by their ready resort to vegetative reproduction.
The Bryophyta and Pteridophyta have sprung from the higher Thallophyta, and together form the larger group Archegoniatae, so-called from the form of the organ (archegonium) in which the egg-cell is developed.
The Mosses and Liverworts include forms with a more or less leaf-like thallus, such as many of the liverworts, and forms in which the plant shows a differentiation into a stem bearing remarkably simple leaves, as in the true mosses.
IFor the histology of the comparatively simple but in many respects aberrant Bog-mosses (Sphagnaceae), see BRYOPHYTA.] The stems of the other mosses resemble one another in their main histological features.
For instance, all the leaves of the Bryophyta are generally homologous inasmuch as they are all developments of the gametophyte.