Volume Ii Part 13 (1/2)

The _Marginellae_ may be divided into two sections; the first bearing in form and habit a strong resemblance to the _Cypraeae_, and the second gradually losing these indications, and acquiring those of the spiral _Volutae_. Among the first are several species, which, like the Cowries, appear dest.i.tute of any spire (as in _M. cingulata_); this part, however, begins to show itself in other successive species very progressively, until it becomes elevated and defined in _M. glabella_. This sh.e.l.l may be considered the pa.s.sage to the second division, in which the species lose the simple oval form of the first, and acquire a contracted base and pointed spire, perfectly resembling _Voluta undulata Lam._ and its allies.

The extreme developement of these characters is shown in _M. faba_.

This genus must, then, be considered as connecting those of _Cypraea_ and _Voluta_ (Lam.); excepting one, the whole of the species are very small; and as the three here selected to ill.u.s.trate these remarks are frequently seen, and have been often described under other names, little more is necessary than to detail their specific characters.

MARGINELLA cingulata,

_Banded Date Sh.e.l.l--upper figures._

_M. testa ovata, albida, lineis aurantiacis fasciata; spira obsoleta, umbilicata; columella 6 plicata._

Sh.e.l.l oval, whitish, banded with orange lines; spire obsolete, umbilicated; pillar 6 plaited.

Voluta cingulata. _Dill._ 525. 56. _Lister._ 803. _f._ 9. _Martini_, 2.

_t._ 42. _f._ 419 _and_ 20. _Gualt._ _t._ 25. _c._? 28. _b._ _Adanson_, _t._ 4. _f._ 4.

I am happy to record Mr. Dillwyn as the first systematic writer who separated this from _Mar. persicula_, which has reddish spots, and is quite a distinct species. The present is a pretty, though common sh.e.l.l, and observed by Adanson in great plenty on the African coast.

MARGINELLA prunum,

_Grey Date Sh.e.l.l--middle figures._

_M. testa ovata, grisea, immaculata; spira parva, conica; apertura fusca; columella 4 plicata._

Sh.e.l.l oval, grey, immaculate; spire small, conic; aperture brown; pillar 4 plaited.

Voluta plumbea. _Sol. MSS. L'Egouen. Adanson_, _tab._ 4. _f._ 3.

V. prunum. _Gm._ _p._ 3446. 33. _Martini_, 2. _t._ 42. _f._ 422 _and_ 3. _En. Meth._ 376. 8. _Lister_, 817. 28. (young.) _Dill._ 530. 69.

The plaits are very strong, and, together with the outer lip, white; equally common, and from the same country, as the last.

MARGINELLA faba,

_Fly-spot Date Sh.e.l.l--lower figures._

_M. testa ovata, plicata, fulva, punctis fuscis ornata; spira conica; basi emarginata; columella 4 plicata._