Shell oval, elongated, equivalve, sub-equilateral, edges almost straight
and parallel; the extremities equally rounded, and as if truncated;
summits but little marked; hinge toothless, or formed by some
rudimentary primary teeth; ligament projecting, affixed to the thick
nymphal callosities; two distant, rounded muscular impressions.
Solecurtus radiatus.
S. strigilatus.
S. legumen.
_S. radiatus._ The radiated Solecurtus.
Species flat, small, with an interior ridge running down obliquely from
the summit to the abdominal margin.
_S. strigilatus._ The strigilated Solecurtus.
Species more cylindrical, without interior ridge.
_S. legumen._ The Pease-pod Solecurtus. Pl. 31, fig. 6.
Species still more elongated and sub-cylindrical.