Note 117 — 5. Genus—PYRGOMA.
Reading edition
Dr. Gray thinks this is the Pyrgoma stellata, of Chenu, (‘Illust. Conch.’); it may be so; but the figure given of the shell will do equally well or rather better for the Pyrgomum dentatum of this work, and for some varieties of P. crenatum. Without a careful description of the opercular valves, it is really impossible to recognise, with any approach to certainty, the species of this genus.