thalloid

Stems thalloid, with large subquadrate succubous leaves; underleaves none.

In thalloid forms fimbriate or lobed margins or outgrowths from the surface lead to the same result.

The protonema forms a flat, lobed, thalloid structure attached to the soil by rhizoids, and the plants arise from marginal cells.

The spore on germination forms a short filament which soon broadens out into the thalloid protonema.

One thalloid form has already been described in Pellia (fig. 2).