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 rotiindata^ Helix pulcJiella^ 
Zua luhrica^ 
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. 
Limax tenellus ; Helix hidentata 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. hiplicata ; 
"^Pupa costulata ; Paludina halthica^ if not our Littorina ulvce ; 
Paludina octona ; "^Paludina similis ; Cyclas lacustris ; Unio 
ater; ^TJnio 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 Sowerhii, Helix fusca. Helix pisana, Helix granulata, 
Amphipeplea glutinosa, Segmentina lineata. 
