HELICIGONA LAPICIDA. 411 
Geographical Distribution.—This species has a very compact range 
in West Central Europe, its area extending from Mid Sweden in the north 
to Cintra in the south, and from Portugal in the west to the north shores 
of Lake Ladoga in the east ; yet it is by no means universally distributed 
throughout the whole region, but is most plentiful in wooded and rocky 
districts, or amongst the mountain ranges, and rare or absent in the low- 
lying plains, and though usually favouring limestone soils, is by no means 
confined to them, as under otherwise favourable conditions it may be found 
living almost indiscriminately on other formations. 
The especial adaptation of this species to a rocky environment results in 
a lessening of its adaptability and power to prosper amidst other more 
generalized surroundings, and thus tends to retard the extension of its 
geographical range. 
(KY Probable Range. BARA Soocrdad DPicrrihution. 
Fic. 468.—Geographical Distribution of Helicigona lapicida (L.). 
H. lapicida has been reported from Germany, Holland, Belgium, France, 
Spain, Portugal, Denmark, Sweden, Norway, Switzerland, Austro-Hungary, 
Poland, Finland, and East Russia. 
It is also recorded from Sicily by M. Locard and others, but the record 
is an improbable one. 
In the British Isles, its natural area of habitation is restricted to the 
eastern counties of Wales, and the south, east, and central counties of 
England, as defined by a line extending from the north-west of Yorkshire 
to the western confines of Devonshire, beyond which are certain outliers 
where the species has been artificially introduced or erroneously recorded, 
as the Orkney Isles and various points in Ireland; but these localities are 
almost certainly erroneous, and do not represent the natural range of the 
species, which is a well defined and continuous tract. 
