- Diagrams of the external form and anatomy of Anodonta cygnea, the Pond-Mussel; in figures I, 3, 4, 5, 6 the animal is seen from the left side, the centro-dorsal region uppermost.
As an example of the organization of a Lamellibranch, we shall review the structure of the common pond-mussel or swan mussel (Anodonta cygnea), comparing it with other Lamellibranchia.
Musculus, diminutive of mus, mouse, applied to small sea fish and mussels), a term applied in England to two families of Lamellibranch Molluscs - the marine Mytilacea, of which the edible mussel, Mytilus edulis, is the representative; and the fresh-water Unionidae, of which the river mussel, Unio pictorum, and the swan mussel, Anodonta cygnea, are the common British examples.
The fresh-water Mussels, Anodonta cygnea, Unio pictorum, and Unio margaritiferus belong to the order Eulamellibranchia of Lamellibranch Molluscs, in which the anterior and posterior adductor muscles are equally developed.
Anodonta cygnea, the Pond Mussel or Swan Mussel, appears to be entirely without economic importance.