LITHOSPERMUM, GROMWELL, in botany, a genus of the pentandria monogynia class. The corolla is funnel-shaped, with a naked perforated fauce; and the calix consists of five segments. There are six species, three of them natives of Britain; viz. the officinale, or gromwell; the purpuro-cæruleum, or lesser creeping gromwell; and the arvense, or bastard alkanet. The seeds of the officinale are accounted diuretic.