stigmarIa

[ Gr.stigma =a mark.] Palæobot .: A pseudo-genus of coal plants, now proved by actual union to be the roots chiefly of Sigil lari a, but in some cases of Lep i do dendron. Cylindrical, trunk-like bodies, often more or le compre ed, the external surface of which is cov ered with shallow pits, sometimes with a rootlet projecting. Very abundant in the fireclay of the carboniferous rocks, the old soil in which the Sigillariæ grew. The common species is Stigmaria ficoides.