06. M. Modiolus, Linn. (Mytilus.)—M. umbilicatus, M. curtus, M. vulgaris.—British coasts generally, C. Large, brown, not rayed.
07. M. ovalis?, Sowb.—M. tulipa (radiata), var., Brit. Moll., now named provisionally. Less tumid, and with longer and more gradually sloped dorsal line than M. radiata, Rr.
08. M. radiata, Hanley, Brit. Marine Conch.—M. tulipa, Brit. Moll., Mc. Tumid, radiated.
09. M. barbata, Linn. (Mytilus.)—M. Gibbsii.—Jersey, Torbay, Milford Haven, Youghal, R. as Brit. Barbs of epidermis serrated.
10. M. phaseolina, Philippi.—Guernsey, Falmouth, Scotland, Mc. Small barbs of epidermis not serrated.
11. M. cuprea, Jeffreys, Ann. Nat. Hist. Jan. 1859.—In the stomach of a bird shot at Scarborough, Rr. Minute, rhomboidal, smooth.
Crenella, Brown.
12. C. nigra, Gray, (Modiola.)—Mytilus and Modiola discrepans, depressa, compressa, discors.—Scotland, R. Broad and compressed behind.
13. C. discors, Linn. (Mytilus.)—Modiola d. and discrepans.—Brit. co. generally, among seaweeds, C. Wedge-shaped and lobed.
14. C. marmorata, Forbes.—Mytilus and Mediola discors, discrepans, and tumida.—Brit. co. generally, Cc. Rhomboidal, marbled.