| Ricinula | Murex. | |
| Purpura, |  | Buccinum. |
| Monoceros, | ||
| Concholepas, | ||
| Harpa, | ||
| Dolium, | ||
| Buccinum, | ||
| Eburna, | ||
| Terebra, |
"To these genera another has been added, called Nassa, of which Buccinum arcularia will furnish an example. The columella has a callosity very evident in the species Pullus and Thersites.
"Ricinula horrida has a ringent aperture of a fine violet colour; the shell is thick, and covered with large black tubercles. The genus takes its name from a resemblance to the seeds of Ricinus.
"Purpura is a large genus: in certain of the species the colouring-matter exists of which the ancients formed their famous purple dye. It is the last genus that offers any appearance of a canal at the base of the aperture.
"P. patula, the scoop, from the Atlantic and Mediterranean, has the aperture remarkably dilated, the margin sulcated.
"P. lapillus is a common British shell among the chalk-cliffs of the coast; the colour varies, sometimes white, at others yellowish.
MONOCEROS.
CONCHOLEPAS.
HARPA.
"I shall describe a species of the singular genus Monoceros, by which you will scarcely fail to recognise it.
"The columella is flattened like Purpura patula; just within the outer lip is a row of small teeth; but the principal peculiarity is a process, or horn, near the outer part of the lower lip, and close to the canal, from which the genus derives its name Monoceros, one-horn. It is brought from the seas of America.
"Concholepas Peruviana, the only species, is also a remarkable shell. The aperture is very large, almost equal to the shell itself; the spire is near the edge; the outside is marked with ribs, or costæ; there are two short teeth on the right-margin. This shell was placed among the Patella.