Geographical Distribution of Mollusca. 



317 



Type of Woodlands. 



1. Ash Wood Formation. 



A — Damp Ash Wood. 



A a — Substituted Beech Wood. 



B — Dry (Copse, Pavements, etc.) 



2. Oak-Birch Wood Formation. 



A — Damp. 



B — Dry and Heathy. 



Note. — In this paper we have adopted the nomenclature 

 of the Conchological Society's List of the British Non-marine 

 Mollusca (1904) with the exception of preferring Pupa for 

 Jaminia as the generic name of this group. 



§ I. Salt Marshlands. Sub-halophile. 

 {a) — Inner zones (or Reed-formation). 



Paludestrina stagnalis Baster, Associated with Littorina 

 rudis Maton. 



A species existing in countless numbers all round More- 

 cambe Bay, in brackish pools at and above high-water mark. 

 The L. rudis is the form known as var. tenehrosa Mont., as usual 

 in brackish waters. 



[h) Transition to Fresh-water Marsh. Sub-halophile. 



Here the soil-water is at most times fresh, rising from land, 

 though at the periods of very high tides it is brackish. 



Succinea oblonga Drap. Associated species : — 



This rare and local species occurs in great abundance near the 

 estuar}^ of the River Winster, at Meathop and towards Grange- 

 over-Sands. In the heat of summer it is to be found at the 

 bottom of the damp drains which intersect the meadows. 

 It is also to be found sparingly among the stones bounding the 

 marshy land, where, in company with LimncBa truncatida, it 

 seems able to exist with a minimum of moisture. It occurs 

 in N. Devon about the dune-marshes of Braunton Burrows. 



COASTLANDS. 



Land. 



A gviolimax Icsvis MiilL 

 agrestis L. 

 Arion circumscriptus Johnston 

 Vitrea radiatula Alder. 

 Punctimi pygmcBum Drap. 

 Hygromia hispid a L. 

 Cochlicopa luhrica MiilL 

 Vertigo pygmcea Drap. 



LinincEa peregev Miill. 



truncatula Miill. 

 Aplecta hypnorum L. 

 Pisidium pus ilium Gmel. 



ohtusale Pfeififer. 



Carychium mininum Miill. 

 Succinea elegans Risso (rareL 



Water. 



1909 Sep. I. 



