203 



A CONTRIBUTION TOWARDS 



A LIST OF THE MARINE MOLLUSCA OF TENBY 



AND NEIGHBOURHOOD. 



By BARTLET SPAN. 



(Read before the Society, March 8th, 1899). 



As I have seen nothing like a complete list of the marine shells that 

 have been found in the above-named localities, I propose to give a 

 list of those species that I have obtained by shore collecting, dredging, 

 and. from trawlers during the past ten yeas. 



As my dredging expeditions have been few I have no doubt that any 

 one who would dredge thoroughly off this coast would be able to add 

 a good many species to those obtained by me. 



The paucity of harbours on this coast, and the dangers of a lee 

 shore from the south-west gales, that spring up so suddenly, and the 

 strong currents that prevail, especially during spring tides, render 

 dredging unpleasant in an ordinary boat. At times the Laugharne 

 and Pendine sands (which extend from the village of Pendine to the 

 Laugharne river, a distance of seven miles) are strewn with shells. 

 Ceratisolen, all the Solenidas (except S. pellucidus), Mactra stul- 

 torum and its variety cinerea, Tellina tenuis, T. balthica, T. fabula, 

 Donax vittatus, Scrobicularia piperata, S. alba, Thracia papyracea, 

 Venus gallina, Philine aperta and Aciceon tomatiUs in thousands, heaps 

 of valves of Lutraria elliptica, a number of Cardium echinatitm, C. 

 edule, Utriculus obtusus, and Hydrobia ulvcs, with an occasional shell 

 of some fifty other species. Some of the specimens found on these 

 sands are of unusually large dimensions as will be seen from measure- 

 ments that I have given elsewhere. 



The list of species is as follows : — 



Anomia ephippium L. — On rocks and stones at low water, spring 

 tides, near Giltar Head. 



Var. squamula L. — With the type. 



Var. aculeata Mull. — On stones and roots of Laminaria. Tenby 

 and Caldy Island. 



Var. cylindricaGm. — On stems of seaweed, Pembrokeshire coast. 



Ostrea edulis L. — The Tenby oysters taken from the beds, off 

 Caldy, and between Caldy and St. Govan, are well-known. 



Pecten pusio L. — My best specimens are from the oyster beds. 

 Valves only from Caldy, Tenby, and Freshwater West. 



P. varius L. — At times plentiful (alive and dead) on Tenby sands. 

 Attached to stones and oyster shells, at Milford Haven. Some of 

 the shells are large, and mostly clean and bright coloured. 



