L. arvense

from The Collaborative International Dictionary of English v.0.48

Gromwell \Grom"well\, n. [Called also gromel, grommel, graymill,
   and gray millet, all prob. fr. F. gr?mil, cf. W. cromandi.]
   (Bot.)
   A plant of the genus {Lithospermum} ({L. arvense}), anciently
   used, because of its stony pericarp, in the cure of gravel.
   The {German gromwell} is the {Stellera}. [Written also
   {gromill}.]
   [1913 Webster]