968 HELIX. 



TENTACULATA. 179. Shell imperforate, ovate-coni- 

 cal, obtuse, with five or six convex whirls, 

 and the aperture sub-ovate. 



Helix tentaculata. Linnaus S]/st. Nat. p. 1249. Pennant 

 Zool. iv. p. 140. t. 86. f. 140. Schroeter Fluss. p. 321. 

 t. 7- f. 19 to 22, and Einl. ii. p. 171. Chemnitz, ix. 

 part 2. p. 175. t. 135. f. 1245. Gmelin, p. 3662. Do- 

 novan, lii. t.93. Montagu Test. p. 389' Maton and 

 Racket, in Lin. Trans, viii. p. 220. Dorset Cat. p. 6Q. 

 t. 21. f. 12. 

 Nerita Jaculator. Muller Verm. ii. p. 185. 

 Turbo Nucleus. Da Costa Brit. Conch, p. 91« t. 5. f. 12. 

 La petite Opercul6e. Geo^roy, p. 114. t. 3. 

 Lister Anim. Ang. t. 2. f. 19, and Conch, t. 132. f. 32. 

 Petiver Gaz. t. 18. f. 8. Gualter, t. 5. f. B. Martini 

 Berlin. Mag. iv. t. 7. f. 12 to 14. 

 Junior. More ventricose, with only four whirls. 

 Helix sphaerica. Gmelin, p. 3627. 

 Nerita sphaerica. Muller Verm. ii. p. 170. 

 Inhabits rivers and ponds ; common throughout Europe. 

 Shell about half an inch long, and half as broad, of a dirty 

 white or horn-colour, frequently covered with a dusky epi- 

 dermis, and sometimes with a calcareous concretion ; it has 

 five or six convex whirls, divided by a deep suture ; the 

 aperture is nearly orbicular, and contracted at the upper 

 end; and it is one of the few British fresh-water shells 

 which are furnished with an operculum. 



REPANDA. 180. Shell sub-iraperforate, ovate, acu- 

 minated, and ventricose ; aperture oval-ob- 

 long. 



Helix repanda. Gmelin, p. 3666. 



Hehx, No. 256. Schroeter Einl. ii. p. 249. 



Buccinum pellucidum, aufractuum quatuor, ore ample. 

 Schroeter Fluss. p. 320. t. 7- f. I6. 

 Inhabits stagnant waters in Thangelstadt. Schroeter. 

 Shell six or seven lines long, and about three broad, with three 



or four whirls, of which the body-whirl is ventricose and 



larger than the spire. Schroeter says the aperture is longish 



oval, and Gmelin's having described it to be semicircular is 



obviously an error. 



CANALis. 181. Shell sub-conical, with five rounded 

 smooth whirls, and the pillar grooved. 



