Few species are known of Eburnæ, and these are neither well defined, nor correctly figured.
EBURNA Valentiana,
Arabian Eburna.
Generic Character.
- Testa turrita, lævis, nitida, umbilicata, basi truncatâ, emarginatâ. Aperturæ angulus superior internè canaliculatus. Animal marinum.
- Shell turrited, smooth, polished, umbilicated, base truncated, emarginate. Upper angle of the aperture with an internal channel. Animal marine.
Generic Type Buccinum Spiratum Lin.
Specific Character.
- E. testâ ventricosâ, maculatâ; aperturæ longitudine spiræ longitudinem superante; spirâ anfractibus 5 convexis, suturis alveatis; basi balteo concavo cinctâ.
- Shell ventricose, spotted; spire shorter than the aperture, of five convex volutions; suture channelled; base with a concave belt.
- Eburna Valentiana. Sw. Appendix to Bligh Cat. p. 6. lot 904.
The species selected by most authors as the type of this genus is Buccinum glabratum of Linnæus, a shell which, as it unites the characters of Eburna and Ancilia, should not have been chosen for this purpose. Types of genera are alone intended to represent the usual appearance of those characters on which the genus has been founded; they should therefore be selected from such species only, as represent these characters in their perfect development.
E. Valentiana was first characterized by myself, in the Appendix to the Bligh Collection. It was brought from the Red Sea by Lord Valentia, in honour of whom it is named. The very short spire and concave belt at the base, easily distinguish this shell from E. spirata.