MITRANÆ. Pl. 6.
1. Mitrella fusca. 2. ocellata. 3. olivæformis.
MITRELLA fusca.
Family Volutidæ. Sub-family Mitriana. Nob.
Generic Character.
Types of form.
1. M. fissuella. 2. casta. bicolor. 3. Olivæformis.
Specific Character.
The natural situation of this group, in its own circle of affinity, has already been shewn; it connects, in the most satisfactory manner, the genus Mitra, as now restricted, with that of Conohelix, and opens at the same time a passage to the Olives. The species yet discovered are few, and hence we yet can only trace three types of form; the first evidently representing Mitra, and the third, probably, typifying Conohelix. M. Olivaria Lam., which truly belongs to this genus, may, perhaps, be only a modification of the 2nd type, to which our present species strictly belongs. The representation of this group among the Volutes, will be found in Voluta Zebra and its allies.
Mitrella fusca is small, and of great rarity; our own specimen, beautifully perfect, is the only one we have yet seen.
MITRELLA ocellata.
This species has probably been overlooked as a variety of M. Fissurella; its markings, indeed, are partially the same, but its sculpture, and even its form, proves it to be distinct. The alternate white and rufous spots bear a fanciful resemblance to eyes. The description of M. Olivæformis has already been given at Pl. 48, in the first volume of our former Series.