372 MOLLUSCA. 



and increasing regularly in width to the end opposite the spire, 

 which is more or less salient, according to the species(l). The 

 animal is not known. The 



VoLUTA, Lin. 



Varies as to the form of the shell and that of the aperture, but is 

 recognized by the emargination without a canal which terminates it, 

 and by the salient and oblique plicae of the columella. From this 

 genus Brugieres first separated the 



Oliva, Brug., 



So named from the oblong and elliptical shape of the shell, the 

 aperture of which is narrow, long and emarginated opposite to the 

 spire, which is short; the plicce of the columella are numerous, 

 and resemble striae; the whorls are sulciform. These shells are 

 quite as beautiful as the Cyprae3e(2). 



The animal has a large fool, the anterior part of which (before 

 the head) is separated by an incision on each side; its tentacula are 

 slender, and the eyes are on their side about the middle of their 

 length. The proboscis, siphon and penis are tolerably long; but it 

 has no operculum. MM. Quoy and Gaymard have observed an appen- 

 dage on its posterior portion, which enters the sulcus of the whorls. 



The remainder of the genus Voluta was afterwards divided into 

 five, by M. de Lamarck(3). The 



VoLVARiA, Lam., 



Closely resembles the Oliva in its oblong or cylindrical form; but 

 the aperture is narrow, and its anterior edge ascends to the top of 

 the spire, which is excessively short. There is one plica, or several, 

 at the foot of the columella. The lustre and whiteness of this shell 

 are such, that on some coasts it is used for making necklaces(4). A 

 small fossil species is found in the vicinity of Paris(5). In the true 

 Volutae or the 



(1) Terebellum subulatum, Lam., Bulla terehellum, L. List., 736, f. 30, Encyc, 

 360,1; — Tereh. convolutum, Lam., Sowerb., Gen. of Shells, No. VL 



(2) Oliv. subulata, Lam., Encyc, pi. 368, f. 6, a, b; — Vol. liiatula, L.; — Vol. 

 porphyria. Vol. oliva, and, in general, all the cylindrical Volutsc of Gm., p. 3438, 

 et seq. 



(3) Exclusive of the Tornatella; and Pyramidelkc already mentioned. 



(4) Voh. monilis, L.; Volv. triiicea. Lam., &c. 



(5) VolvariabuUo'ides, Lain., Encyc. Method., pi. 384, f. 4. 



