Those in the outer whorl, opposite the sepals, are longer.

Ribs are irregular, straight at first, becoming denser and sigmoid on the outer whorl.

The tepals in the outer whorl tend to be green on the outside.

The shell is evolute and ribbed, with the outer whorls becoming smooth.

Ribs on the outer whorls become free of tubercles and end up all smooth.

The shell is compressed with the outer whorl covering much of the previous.

The shell is ornamented with nodules which either persist or die out in the outer whorls.

The outer whorl consists of large tentacles that extend outwards.

The outer whorl may be costate or have rows of nodes, or both.

The outer whorl embraces most of the inner, leaving a small umbilicus.