18 SCIENTIFIC SURVEY OF BLACKPOOL AND DISTRICT 



Littorina saxatilis (Olivi). (Littorina rudis, Don.) 

 Littorina littoralis (L.). {Littorina obtusata, Linn.) 

 Turritella communis Risso. (Turritella terebra, Linn.) 

 Aporrhais pespelicani quadrifidus da C. (Aporrhais pespelicani, 



Linn.) 

 Natica catena (da C). 

 Trivia sp. (Cypraea Europaea, Mont.) 

 Trophon clathratus L. 



Nucella lapillus (L.). (Purpura lapillus, Linn.) 

 Ocenebra erinacea (L.). (Murex erinaceus, Linn.) 

 Neptunea antiqua (L.). (Fusus antiquus, Linn.) 

 Buccinum undatum L. 



Nassarius reticulatus (L.). (Nassa reticulata, Linn.) 

 Nassarius incrassatus (Strom). (Nassa incrassata, Miiller) 

 Lora turricula (Mont.). (Pleurotoma turricula, Mont.) 

 Lora ruja (Mont.). (Pleurotoma ruja, Mont.) 

 Lora pleurotomaria (Couth.). (Pleurotoma pyramidalis, Strom) 

 Mangelia nebula (Mont.). (Pleurotoma nebula, Mont.) 

 Dentalium entalis L. 

 Nucula sp. 

 Mytilus edulis L. 

 Ostrea edulis L. 



Chlamys opercularis (L.). (Pecten opercularis, Linn.) 

 Astarte sulcata (da C). 



Cyprina islandica (L.). 



Cardium aculeatum L. 



Cardium echinatum L. 



Cardium tuberculatum L. 



Cardium edule L. 



Callista chione (L.). (Venus chione, Linn.) 



Macoma balthica (L.). (Tellina Balthica, Linn.) 



Gari fervensis (Gm.). (Psammobia Ferrdensis, Chemn.) 



Mya truncata L. 



Hiatella gallicana (Lam.). (Saxicava rugosa, Linn.) 



Zirfaea crispata (L.). (Pholas crispata, Linn.) 



All these are salt-water species, and only five are unknown on the Lancashire 

 coasts to-day. 



After the deposition of the Upper Boulder Clay, streams washed shingle out 

 of the clay and caused it to collect in several small areas, notably at PreesalL 

 from which the deposit has derived its name of Preesall shingle, and several 

 small patches west and south-west of Garstang. 



As the surface of the Upper Boulder Clay was a surface of deposition, not of 

 erosion, there are in its surface numerous swamp hollows without outlet. 

 They are covered with peat deposits, often thick, which also occupy several 

 other large ill-drained areas, such as Pilling and its associated mosses. 



The present surface of the peninsula west of the Wyre, between that river 

 and the coast, north of an irregular west-east line about a mile north of 

 Norbreck, now consists of tidal alluvium, as also does the area between the 



