ZONITES. 167 



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

 as the H. nitidosa of Ferussac and H. striatula of Gray ; 

 but both these latter names were unaccompanied 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, Mull. 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 

 interspersed 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 semiglobular, 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 : whorls 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 penulti- 

 mate whorl contracts it : outer lip rather obliquely 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. albida. 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. 



T 



