ZONITES. 167 



It is the Helix nitidula, var. 13, of Draparnaud, as well 

 as the H. nitidosa of Ferussac and H. striatula of Gray -, 

 but both these latter names were nnaccompanied by de- 

 scriptions. The H. striatula of Linne, Miiller^ and Olivi 

 are different from that of Dr. Gray and from each other. 



6. Z. ni'tidus*, Miiller. 



Helix nitida, Miill. Verm. Hist. pt. ii. p. 32. Z. nitidus, F. & H. iv. p. 39, 

 pi. cxx. f. 4, 7. 



Body strongly truncate in front, bluish-black or dark- 

 brown, covered with large round flat tubercles which are in- 

 terspersed with a few minute milk-white specks : snout small, 

 short, broad, and tumid : tentacles rather thick and short ; 

 bulbs globular: foot obtusely rounded in front, narrow and 

 somewhat keeled behind. 



Shell semigiobular, much more convex above than below, 

 not very thin, but glossy and semitransparent, chocolate- 

 brown, marked transversely by numerous curved striae which 

 are stronger and puckered towards the suture, and very finely 

 granulated under the microscope: epidermis rather thin: 

 ivhorls 5, convex, the last occupying about one-half of the 

 shell: spire somewhat prominent, with a blunt point: suture 

 deep : mouth round, except where the penultimate whorl con- 

 tracts it : outer lip rather obhquely set, thin, and reflected near 

 the pillar : umbilicus narrow, but deep, exposing all the interior 

 of the spire. L. 0-1. B. 0-275. 



Var. alhida. Shell white or colourless. 



Habitat : Under loose stones and decayed wood, as 

 well as at the roots of grass and on mud in bogs and 

 moist places, from the North of Scotland to Guernsey. 

 Specimens of the variety were found by Mr. Choules 

 among the rejectamenta of the Thames at Richmond. 

 Although dead shells, they have not become bleached 

 by exposure to the sun. A monstrosity also sometimes 

 occurs, in which the whorls are slightly disunited, as in 



* Glossy. 



