OLIVÆ PL. 3.
Hiatula Lamarci 2. pallida. 3. maculata.
As the connection of the Olives with the Mitres has been illustrated in a former number, we now characterize the sub-genus by which the former are united to the Ancillariæ. The thickened and oblique plaits on the pillar, its smoothness on the upper part, and the great width of the aperture, are all characters which render this affinity unquestionable, and detach the group from the more common and typical Olives before alluded to.
OLIVÆ. Pl. 3.
The Wide-mouthed Olives.
Family Volutidæ. Genus Oliva. Nob.
Sub-Genus Hiatula. Nob.
Suture channelled. Pillar above smooth, not thickened, beneath tumid, and marked with a few oblique plaits: base of the aperture very wide.
Specific Characters.
Hiatula Lamarci. Fulvous brown: pillar white, with about four lengthened plaits, and intermediate shortened ones between them, inner margin of the lip brown. Fig. 1.
H. pallida. Aperture and base of the pillar livid brown: plaits 4-5, simple, equal; inner margin of the lip pale. Fig. 2.
H. maculosa. Aperture orange, marked above with a black spot: base of the pillar white, the plaits small, crowded, and of unequal length. Fig. 3.
Mus. Nost.
Since we published the figure of Oliva striata, (Oliva, Pl. 1. f. 2.) we have procured the true Ancillaria canalifera of Lamark, and find it as we suspected, a very different shell. As Hiatula leads to the Ancillariæ, so does the sub-genus Olivella, (comprising the small operculated Olives) conduct us to the Mitres, by means of Olivella volutella, already figured in this work. We believe the third aberrant form is represented by our Oliva striata, but we shall not proceed to characterize it as a sub-genus, until a better acquaintance with the group is obtained; its analogy to Conohelix, by its external sculpture, seems to us a strong ground of distinction.
We procured all these wide-mouthed Olives from the Messrs. Stuchbury, to whom we are often indebted for the loan of interesting specimens.