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

by G. B. Sowerby

22. P. pusillum, Turton, (Tellina.)—Cyclas fontinalis and gibba.—In marshes and ponds at various places, C. Includes P. obtustale?

23. P. amnicum, Müller, (Tellina.)—T. rivalis, Cyclas palustris, C. obliqua.—British rivers, etc., generally. C. obliqua ribbed.

24. P. nitidum, Jennyns.—Battersea, Swansea, etc., C. Thick, dark, blunt.

25. P. Henslowianum, Sheppard, (Tellina.)—Cyclas appendiculata, P. acutum.—Cambridge, Swansea, etc., R. With a projection on the umbones.

26. P. pulchellum, Jennyns.—Cyclas fontinalis, etc.—Various localities, C. Ridged.

27. P. cinereum, Alder.—Cyclas c.—Various localities, Mc. Smooth.

28. P. roseum, Scholtz.—Various loc., with P. pulchellum and P. nitidum M. C. Subquadrate; animal pink.

PLATE VII.