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

by G. B. Sowerby

23. O. diaphana, Jeffr. Ann. Nat. Hist. New Ser. vol. ii. p. 341.—R. Manifestly distinct from No. 22.

24. O. strialata, Alder.—Northumberland, Rr. Conical, striated.

25. O. minima, Jeffreys, Ann. Nat. Hist. Jan. 1, 1858.

26. O. interstincta, Mont. (Turbo.)—T., O., Voluta, and Jaminia canaliculata, oblonga, and obtusa.—Brit. co. generally. Shallow water, C. With longitudinal ribs.

27. O. dolioliformis, Jeffr.—Scarborough, Exmouth, Swansea, Tenby, Rr., Scotland. Oval, body-whorl very tumid.

28. O. Warrenii, Thompson, (Rissoa.)—Turbonilla and O. obliqua, O. decorata.—Dublin, S. Devon, W. Scotland, R. Turreted. Mouth oblique; an umbilicus; no fold or columella.

29. O. spirialis, Mont. (Turbo.)—Voluta and Rissoa s., pellucida, and plicatula.—Brit. co. generally, not deep, Mc. Whorls ribbed longitudinally above, spirally beneath.

30. O. decussata, Mont. (Turbo.)—T. Helix, Rissoa and O. arenaria, pellucida?, and d.—Exmouth, Lerwick, etc., R. Ribbed and spirally striated.

31. O. excavata, Phil. (Rissoa.)—R., O., and Cingula Harveyi and Deshayesiana.—Dublin, Arran, Guernsey, R. Largely sculptured.