Seed triangular, about 6-10 mm. long, with a broad apex, and two wellmarked horns at the angles of the apex. A median ridge extending from the apex to base is prominent on most specimens. Testa smooth.
The species now represented, occurs, occasionally in the shale, and always, or, at least, most commonly, in groupes; as is the case in the present instance. This circumstance makes it probable that they were clustered together when they were growing on the plant and that they were either deposited where they grew or that they had been drifted but a short distance. Each grain is lenticular always acute at one end and sometimes so at the other, but more generally obtuse. The acute end (d) appears to have been the apex and the obtuse end the base.
morphospecies
type: Cardiocarpus acutus in: Lindley and Hutton, 1833, vol. i, p. 209, Pl. LXXVI.
