S. cultellus. The kidney-shaped Solen.
Species a little curved lengthwise; summit not terminal.
S. rostratus. The violet-beaked Solen.
Species with longer and narrower valves, flatter at the extremities; callosity at the hinge very visible; cardinal teeth or hinge nearer the middle than the anterior side.
S. ensis. The Sabre Solen.
Species linear, sabre-shaped; a single compressed tooth in each valve; olive brown at the base, and of a purple hue near the apex.
S. siliqua. The podlike Solen.
Species linear, straight; two teeth in one valve and one in the other; covered with a glossy brown epidermis; striated transversely.
S. antiquatus. The Antiquated Solen.
Species thin, white, and almost transparent; striated concentrically; ends rounded; hinge near the centre; a tooth in one valve locking into two in the other; the teeth erect and projecting beyond the margin; covered with a dark-coloured epidermis.