Isabella-colour, a brownish yellow with a shade of brownish red.
Juncture, the joining of the whorl in univalve shells.
K.
Keel, the longitudinal prominence in the Argonauta.
Knob, a protuberance, any part bluntly arising above the rest.
L.
Labra, the lips.
Laciniate, jagged or cut into irregular segments.
Lacunose, having the surface covered with pits.
Lamellar, consisting of films on plates.