48 LINNEAN GENERA. 



little oblique ; apex obtuse ; aperture sub-orbicular, witb a thick 

 sulcated margin. 



Found on the Coasts of Pembrokeshire, Dorsetshire, and Nor- 

 thumberland. 



R R R R. Ribs. 



Turbo labiatus The Lipped Turbo. Plate III. fig. 13. 



(Clausilia labiata, Lamarck.) Shell with nine reversed volu- 

 tions or whorls, tapering to a fine point ; colour light brown> 

 with strong, regular, longitudinal striae ; volutions flat, and se- 

 parated by a fine obsolete line ; aperture sub-orbicular and white, 

 with a sinus at the upper end, and two teeth-like laminae on the 

 inner lip ; margin reflected, broad and thick. Found in Hyde 

 Park, and the ozier grounds at Battersea in Surrey. 



Plate III. fig. 13. B Reversed or heterostrophe spire, a teeth of a univalve. 



The shells of this genus inhabit the sea, land, and fresh water ; they ad- 

 here to rocks near the shore ; and some of them live in very deep water. 



The Turbo Scalaris, or wentletrap, is very much esteemed by collectors, 

 and is rather a scarce shell. 



Genus 29.— HELIX. 



Animal a Limax ; shell univalve, spiral, subdiaphanous, brit- 

 tle ; aperture contracted^, semilunar or roundish. 



Linne divides the Keiices into six families : *angulated on both sides ; 

 ** whorls with a cariuate acute margin; ***whorls rounded and urabili- 

 cated; ****rounded and imperforate; *****tapering; ******ovate and 

 imperforate. 



Helix arbustorum. — The Grove Helix. Plate IX. fig. 29. 

 Sub-globose, sub-pellucid, with five volutions ; mottled with ash- 

 colour, and streaked with deep chestnut zigzag lines ; a single 

 deep brown band commences at the edge of the outer lip, and 

 continues round the middle of the body and the volutions to the 

 apex ; fths of an inch in diameter. Inhabits groves in Britain. 



Helix vivipara. — The Viviparous Helix. Plate II. fig. 

 8. (Paludina vivipara, Lamarck.) Shell with six ventricose 

 whorls, separated by a deep depressed line ; sub-ovate and obtuse; 

 of an olive-green, with generally three fasciae or bands on the bo- 

 dy of the shell, and two on the superior volutions, which become 

 obscure in the fourth ; slightly wrinkled transversely ; aperture 

 sub-orbicular ; pillar-lip reflected : sub-umbilicated. Found in 

 the Thames and New River. 



A Apex, B base, l a whorl, r r bands or fasciae. 



