Cordate, heart-shaped.

Cordiform, resembling the form of a heart.

Coriaceous, of a leather-like consistence.

Corneous, of a horn colour, resembling a horn.

Coronal, relating to the crown or top.

Coronated, crowned, or girt towards the apex.

Costated, ribbed, having large ribs.

Corpus, the body of the shell, the last or great wreath in which the aperture is situated.

Cortex, the anterior skin or epidermis.

Crenulated, notched at the margin, scalloped.