GEOGRAPHICAL DISTRIBUTION. 297 



markable that in our more northern latitudes, as compared 

 with France, there are found in abundance some species, such 

 as Helix pisana and Bulimus acutus, which for their size and 

 colour are only to be compared to the French specimens found 

 on the banks of the Loire. 



On the other hand, there are many species, not found in our 

 catalogues, that are common to nearly all the rest of Europe. 



Thus, according to Nilson, 73 of our British species are 

 found in Sweden, and many of them, as, for example, 

 Helix pygmea, Helix fulva, Helix rotundata, Helix pulchella, 



Zua lubrica, 



at its most northern extremity ; and he has, in his Fauna, 

 16 species which have not yet been found in Britain or Ire- 

 land : viz. 

 Lirttax tenellus ; Helix bidentata Nilson, not Gmelin ; * Helix 



fruticum ; *Helix strigella ; * Helix incarnata ; *Helix conspur- 



cata ; * Helix ericetorum Nilson, not Linn. ; H. candidula 



Studer ; Clausilia papillaris, if it is not our C. biplicata ; 



*Pupa costulata ; Paludina balthica, if not our Littorina viva ; 



Paludina octona ; * Paludina similis ; Cyclas lacustris ; Unio 



ater; * Unio crassus Nilson; U. littoralis, Lam.; Unio limosus. 

 And of these at least half (those marked with a star) are also 

 common to France and to Germany ; and this may be the case 

 with some of the others. Some of these species (of Helix, for 

 example) are of a size as large as H. hortensis and H. rufes- 

 cens ; and the largest, as H.fruticum, H. strigella, and H. can- 

 didula, are found as far south as Vienna, and H. incarnata as 

 far as Italy. Indeed, some of the Continental conchologists 

 appear to upbraid our idleness in not having found them 

 in England, where, probably overlooking our insular position, 

 they assume that these species ought to be found. 



Nearly three fourths of our species, that is to say 91 out of 

 the 126, are recorded by Pfeiffer as inhabiting Germany; and 

 the Germans have 80 species which are wanting to our Fauna ; 

 but it is remarkable that they have not some of our larger 

 species, as 

 Limax Sowerbii, Helix fusca, Helix pisana, Helix granulata^ 



Amphipeplea glutinosa, Segmentina lineata. 



