36 INTRODUCTION. 



Helix Cantiana has been supposed to be almost 

 confined to the four metropolitan counties, but it is 

 also found in Suffolk, near Bristol, and near Dublin. 

 It may have been introduced in these latter localities 

 for it has been within these few years, according to 

 Mr. Fryer, introduced with ballast by the colliers on 

 the banks of the Tyne ; and is now rapidly spread- 

 ing itself in the hedges of that neighbourhood. These 

 circumstances would lead one to imagine that it might 

 also have been introduced into England from the 

 Continent ; but Ferussac, who has compared it with the 

 continental species, regards it at least as a local variety 

 of H. Carthusiana of Draparnaud (not of Muller), 

 which is a native of the south of France and Italy. 



Helix Carthusiana Muller, is confined to the 

 downs (especially those bordering the sea) of Kent 

 and Surrey, where it is found in abundance on the 

 short stunted grass : it is also found in the south of 

 France, Greece, and Syria. 



Helix aperta and H. revelata have as yet only been 

 found in the island of Guernsey, where they were 

 discovered by Mr. Edw. Forbes. This island is 

 nearer the coast of France than that of England, and 

 is geographically part of the former country. The first 

 species is a native of Provence, and is not yet recorded 

 as found in the northern part of France ; Guernsey 

 must be considered its northern limit, but it is a very 

 shy species, and difficult to find, even in Provence, ex- 

 cept after a shower of rain. The H. revelata is found 

 in Normandy, and near Paris. 



Bulimus acutus is found in similar situations to 

 H. virgata and H. Carthusiana^ especially in sandy 

 places ; but it is confined to the south-western coun- 



