E.

Echinated, bristled like a hog, set with spines.

Effuse, spread out.

Elliptical, having the form of an ellipsis, oval.

Elongated, lengthened, drawn out.

Emarginate,  } with the edge or margin notched.
Emarginated, }

Ensiform, sabre-shaped.

Entire, whole, uninterrupted, not divided.

Epidermis, the outer coating or scarfskin of the shell.

Equidistant, being at the same distance.

Equilateral, having all sides alike.

Equivalve, having both valves of equal dimensions.

Exolete, worn or faded.

Exserted, standing out, protruding.

Extraneous, not belonging to a particular thing.