Longmynd rocks

Long´mynd rocks´


n. pl.1.(Geol.) The sparingly fossiliferous conglomerates, grits, schists, and slates of Great Britain, which lie at the base of the Cambrian system; - so called, because typically developed in the Longmynd Hills, Shropshire.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.