114 VULSELLA. 
VERRUCA. Schum. Curria, Leach. 
VIRGULINA. D’Orb. A genus of microscopic Foraminifera. 
VITRINA. Drap. (Vitreus, glassy.) Fam. Limacinea, Lam. and 
Bl. Deser. Ovate, thin, glassy, fragile; spire short; last whorl 
large; aperture wide, transverse; peritréme simple; columella 
spiral, linear. Obs. This genus of land shells is not known in a 
fossil state. The recent species are found among moss and grass 
in shady situations: De Ferussac has divided this genus into 
Helicolimax, fig. 263, and Helixarion, fig. 262. 
VIVIPARA. A generic name given by some authors to Patu- 
pina, Lam. on account of the animals being viviparous, i. e. the 
young being perfectly formed before they leave the ovaries. 
VOLVARIA. Lam. (Volva,a shuttle.) Fam. Columellaria, Lam. 
Deser. Cylindrical, convolute, spirally striated ; spire very short, 
nearly hidden; aperture narrow, as long as the whole shell; co- 
lumella, with three oblique plaits; outer-lip dentated. Obs. 
The Volvariz, are only known in a fossil state, and resemble 
some species of Bulla in general form, but are distinguished by 
the plaits of the columella. Fig. 439, V. concinna. 
VOLUTA. Linn. (Volvo, to revolve.) Fam. Columellaria, Lam. 
Angyostomata, Bl. Deser. Sub-ovate, rather angulated, thick, 
generally tuberculated, smooth ; spire short, conical, with a mam- 
millated apex; aperture generally angulated, large, terminating 
anteriorly in a deep notch ; columella smooth, with several plaits, 
of which the lowest is the largest; outer-lip thickened within, 
Obs. This genus includes a great number of beautiful shells, 
most of which are rich in colouring. Cympa and Meno have 
been separated by Mr. Broderip, from the genus Voluta, of La- 
marck, for reasons stated in their respective descriptions. Fig. 443. 
VOLUTELLA. Sw. (A hitle volute.) A genus composed of those 
species of Maremetia, Auct. which have the spire concealed, 
and the aperture smooth within. Fig. 438, Persicula of Schu- 
. macher. 
VOLUTION. v. Wuort. 
VOLUTILITHES. Sw. (Voluta, and diées, lithes, a stone.) A 
- genus composed of some fossil species of Votura, which have 
the plaits on the pillar generally numerous, indistinct, and some- 
times wanting altogether, with a pointed spire. Fig. 436, V. 
spinosa. 
VORTICIALIS. Lam. A genus of microscopic Foraminifera. 
VULSELLA. Lam. (A little tongue.) Fam. Ostracea, Lam. Mar- 
garitacea, Bl. Descr. Equivalve, irregular, longitudinal, com- 
pressed, oblong; umbones separated by a slight area in both 
valves; hinge with a large pit in the centre, containing the car- 
tilage, the ligament being spread over the areas; muscular im- 
pressions, one in each valve, sub-central, oblong. Obs. This 
genus differs from Ostrea, in the equality of the valves, and in 
