# Zoological Illustrations/VolI-Pl42

OLIVA Braziliana.
Brazilian Olive
Generic Character.
    Testa cylindrica, polita; spira conica, acuminata, brevissima; labium exterius simplex, interius incrassatum, tumidum; columella plicis numerosis gracilibus; apertura basi truncata, emarginata.
Typus Genericus Voluta Porphyrea Lin.
    Shell cylindrical, polished, spire conic acuminated, very short; outer lip simple, inner lip thickened, tumid, columella with numerous slender plaits, aperture at the base truncatedly emarginate.
Generic Type Voluta Porphyrea Lin.
Specific Character.
    O. testâ coniformi, latâ; aperturâ effusâ, labio interiore tumidâ callositate super spiram extendente.
    Shell coniform, broad; aperture effuse, tumid callosity on the inner lip large, and spreading over the spire.
    Oliva Braziliensis. Martini p. 130, tab. 147 & 8, 1367 & 8.
    Oliva Braziliana. Lamarck.
    Voluta pinguis. Dill. 516. 36.
No family of shells possess characters more strikingly obvious to common observers than the Olives; and yet, although in our English terminology no one would ever think of calling them Volutes, we still shrink from giving them that distinguishing appellation in Latin which we every day use and acknowledge in our own language. The strict followers of Linnæus, by thus rejecting generic distinctions, which at once convey a definite idea of form and structure, contribute to render systematic arrangement less expressive of ideas than the common nomenclature of our sale catalogues: a striking proof of the pertinacity with which we cherish those particular doctrines we first imbibed, although an unbiassed reasoning and an attentive observance of nature would convince us of their fallacy.
The great Linnæus, at the time he formed that system which laid the foundation of systematic nomenclature, had not the materials for gathering and combining those natural genera which the immense discoveries made since his death have given us a knowledge of. He accordingly arranged those few shells known to him, in large, and for the most part natural, groups. That of Voluta I consider as one of these last (excepting the first division); but the great accession of species now known, and which is still increasing, has long ago induced the principal Continental writers to divide this very extensive family into the following genera: Marginella (Date shells), Oliva (Olives), Mitra (Mitres), Turbinellus (Turnip shells), Voluta (Volutes), ...; all possessing not only clear but natural characters; inasmuch as, by such an arrangement, those interesting links and ramifications that connect this family with the Bullæ, Cones, Cowries, Murices, and other genera, can be traced; and which perhaps affords the most fascinating and intellectual source of contemplation and study the science can bestow.
The peculiarity of this species will distinguish it among this numerous and intricate family. The basal suture is deeply channeled; those on the spire covered by the polished callosity which spreads from the inner lip.
Mr. Dillwyn has adopted the unpublished name of Solander, although the shell had long ago been described and named by Martini and Lamarck. I consider this as contrary to that principle of nomenclature which awards a preference to priority of publication; and I have therefore restored the name of those authors who have this undoubted claim. Mr. Dillwyn's description is very clear and good.
I cannot learn from what particular part of Brazil this species has been received.