Denticulated, set with small teeth, as in the Arca.
Depressed, pressed down horizontally, low, shallow, flat.
Dexter valve, is the right valve.
Diaphanous, transparent, clear, pellucid.
Digitated, fingered or clawed, as in the lobes of the outer lip of the Strombi, &c.
Disk, the middle part of the valves, or that which lies between the umbo and the margin.
Divaricated, straddling, spreading out widely.
Divergent, tending to various parts or directions from one point.
Dorsum, the back; it generally means the upper surface of the body of the shell, when laid upon the aperture or opening. In the genera of Patella and Haliotis, the back means the upper convex surface.
Dotted, punctured like a thimble.