The Conchologist's First Book / A System of Testaceous Malacology, Arranged Expressly for the Use of Schools, in Which the Animals, According to Cuvier, Are Given With the Shells, a Great Number of New Species Added, and the Whole Brought Up, as Accurately as Possible, to the Present Condition of the Science.

by Edgar Allan Poe; Thomas Brown

M.

Margin, the whole circumference or outline of the shell in bivalves.

Marginated, having a prominent margin or border.

Membrane, a web of fibres.

Mouth, see Aperture.

Muscular impressions, marks made by the animal in adhering to the shell.

Mottled, clouded or spotted.

Mucronate, ending in a sharp point.

Multilocular, many chambered.

Muricated, clothed with sharp spines.