50 
* V. EDENTULA. Gray’s Turt., p. 199, pi. 7, fig. 80. 
Locally common. 
V. PY GM/E A. Turbo Sexdentatus, Junior. Mont. Test- 
Brit., vol. 2, p. 337, pi. 12, fig. 8. V. P. Gray’s Turt., 
p. 202, pi. 7, fig. 83. Montagu found it in a boggy place 
in Cornwall, on the yellow water flag; and I believe 1 
found it in a pond at Pontuan. 
BAL7EA. 
GENERIC CHARACTER: The shell reversed, thin, with 
a lengthened, taper snire, the last volution larger than the 
next, aperture roundish oval, entire at the base, oblique, 
with a single tooth on the pillar, which is wanting in the 
young shells, and the pillar is destitute of any valvclike 
plait or ciausiuni. From Buliinus and Pupa this genus 
is distinguished by the aperture being left handed ; front 
Clausilia in having the ultimate volution proportionately 
larger than the next; and from Vertigo, in the regularity 
of its mouth. From the young of Clausilia it may be 
known by the front of the last whorl being convex and 
simple, not flattened and furnished with a keeled ridge 
near the outer edge. Gray. 
* B. PERVERSA. Turbo P. Mont. Test. Brit,, vol. 3, 
p. 355. pi. 11, fig. 12. B. P. Flem. Brit. An., p. 271' 
Gray’s Turt., p. 207, pi. 6, fig. 70. Common. 
CLAUSILIA. 
GENERIC CHARACTER: The shell reversed, with * 
. lengthened, slender, spindle formed spire, the last volution 
less tumid than the one before it, with an obtuse or p a ' 
pillary summit; aperture oval, oblique, united all round 
and margined, toothed ; throat with an internal spiral 
shelly plait (elausium) fixed on an elastic pedicle, which 
closes the cavity when the animal is withdrawn. 
* C. BIPLICATA. Turbo B. Mont. Test. Brit., vol. 3, 
p. 361, pi. 11, fig. 5. C. B, Flem. Brit. An., p. 271- 
Gray’s Turt., p. 214, pi. 5, fig. 55. Common. 
C. NIGRICANS. Turbo Bidens. Turt. Lin. T. Pervei" 
sus. Pen. Brit. Zo., vol. 4, pi. 82, fig. 116. T. B. Moot- 
Test. Brit., vol. 2, p. 357, pi. 11, fig. 7. C. Perversa- 
Flem. Brit. An., p. 271. C. N. Gray’s Turt., p. 2l?> 
pi. 5, fig. 53. Not common within my observation. 
A U RICULID/E. 
Is a family instituted by Mr. Gray, and chiefly chara®' 
terized by peculiarities in the animal: “which has aI J 
elongated foot, an elongate ringed muzzle, two subeylindricaj 
tentacles with the eyes near the inner side ( that is, place 
behind instead of in front of) their base ; body spiral, pl aC ® 
