venus. 287 



also been applied to any swelling ridge, sack as that on the lower 

 part of the columella of Ancillaria, fig. 456. 



VELATES. Montf. Neritina perversa, Auct. Fig. 326. 



VELLETIA. Gray? A genus described as differing from A ncylus 

 in being dextral. Velletia lacustris, Ancylus lacustris, Auct. 

 fig. Sowerby Gen. fig. 2. 



VELUTINA. Auct. Fam. Macrostomata, Lam.— Bescr. Sub- 

 globose, covered with a velvety epidermis ; spire short, composed 

 of two rapidly enlarged ventricose whorls ; aperture large, sub- 

 ovate ; peritreme thin, entire, separated from the last whorl ; 

 columella tortuous, thin. — Obs. This shell does not resemble any 

 other genus in the family. Fig. 337. Northern Seas. 



VENERICARDIA. Lam. A genus composed of the shorter species 

 of Cardita. 



VENERIRUPIS. Lam. (From Venus and rupis, a rock.) The 

 oblong species of Venus Auct. which live in cavities of rocks and 

 stones. This genus is united by Sowerby with some other species 

 of Venus under the name Pullastra. V. Vulgaris, fig. 97. 



VENTRAL. (Venter, the belly.) The margin of a bivalve shell 

 opposite the hinge. The under valve in Brachiopodous bivalves 

 is the ventral valve. The ventral surface of an univalve spiral shell 

 is that which faces the observer when the aperture is placed 

 towards him. The ventral part of the whorls of symmetrical 

 convolute shells, is the inner part, that which is nearest to the 

 spire. 



VENTRAL SIPHON. In symmetrical convolute univalves, is one 

 placed near the inner edge of the whorls. 



VENTRICOSE. {Ventricosus .) Swelled, rounded out, (homU Fr.) 

 as Harpa ventricosa, fig. 419. 



VENUS. Auct. (Goddess of Beauty.) Fam. Marine Conchacea, 

 Lam. Conchacea, Bl. — Bescr. Equivalve, inequilateral, sub-glo- 

 bose, sub-ovate, transverse, externally rugose, striated, ribbed, 

 cancellated or smooth ; margins entire, simple, close ; hinge 

 with three more or less distinct cardinal teeth, diverging from the 

 umbones in each valve; muscular impressions two, lateral, distant ; 

 palleal impressions sinuated posteriorly ; ligament external. — Obs. 



