Thin cakes called Crumpits, made from seeds of Polygonum aviculare L. (Knot Grass)

Came across an early mention of Crumpets - in a herbarium !

Culinary uses of Polygonum aviculare L. (Knot Grass): 'The Seeds furnish a nutritious meal; it
is made into thin cakes called Crumpits.'

a small extract in a fascinating article by Jessica Shepherd, Natural History Research Assistant (St. Aubyn)

Bringing a herbarium to life at Plymouth City Museum and Art Gallery

Plymouth City Museum and Art Gallery via a grant from the Esmée Fairbairn Foundation