Illustrated Index of British Shells / Containing figures of all the recent species

by G. B. Sowerby

26. N. costellata, Desh.—Corbula c., N. sulcata.—Loch Fyne, Rr. Radiately 3-ribbed.

27. N. cuspidata, Olivi.—Forth, Northumberland, Cape Clear, etc., Mr. Pear-shaped.

28. N. abbreviata, Forbes.—Loch Fyne, Mc. Radiately 1-ribbed.

PLATE II.

Poromya. On mud, in deep water.

Fig.

01. P. granulata, Nyst.—P. anatinoides, Forbes.—Skye, R.

01*. P. subtrigona, Jeffreys.—Shetland, Mr. Minute, posteriorly expanded. See Pl. IX.