Значения термина ancylus на английском

All this alluvium was evidently of fluviatile origin, for, in the interstices between the pebbles, the Ancylus fluviatilis and other freshwater shells were abundant.

Mr. Roper shot some ducks, and I found a species of Ancylus; besides the species of Limnaea and Paludina, which we had previously met with.