A. rubens.
A. crispata.
A. uniopsis.
A. Pennsylvanica.
A. intermedia.
A. glauca.
A. sinuosa.
A. Patagonica.
A. cygnæa. The Swan Anodonta. Pl. [11], fig. 2.
Species oval, thin, elongated, hinge straight, and only auriculated anteriorly; beaks small and ventricose; concentrically wrinkled; covered with a greenish epidermis, which is frequently of a brown tinge towards the umbo.