2 94 SMART AND COOKE : MARINE SHELLS OF SCILLY. 



Pandora inaequivalvis var. obtusa L. — Two specimens 

 only from the Menavawr and Round Island dredgings. 



Thracia prastenuis Pult. — Living in sand, low water, spring 

 tides, St. Martin's Flats, but very rare. 



T. papyracea Poli. — Abundant in the sandy bays. 



T. distorta Mont. — Four or five single valves from St. Mar- 

 tin's Flats and dredgings. 



Corbula gibba Olivi. -^Gregarious in muddy sand, Crow 

 Sound and elsewhere. 



Saxicava rugosa L. — Under rocks below Cromwell's Castle, 

 and probably everywhere ; also dredged outside Mena- 

 vawr. 



S. rugosa var. arctica L. — Plentiful in deep water dredgings. 



Venerupis Irus L. — Three valves only; one off beach at 

 Guthers, two from deep dredgings. 



Gastrochoena dubia Penn. — A single valve from the 

 Menavawr dredging. 



Xylophaga dorsalis Turt. — One valve only, with the pre- 

 ceeding. 



Dentalium entalis L. — Three or four specimens from muddy 

 sand, Crow Sound. 



Chiton cinereus L. — From the Menavawr dredgings, on 

 stones and old shells, not uncommon. 



C. marginatus Penn. — Under loose stones on the shore; 

 not common. 



Patella vulgata L. — Exceedingly abundant everywhere, and 

 of every shape and size. 



P. vulgata var. depressa L. — With the type. 

 Helcion pellucidum L. — On Laminaria, fairly common. 



Tectura virginea Mlill. — From the Crow Sound dredgings, 

 and thrown up on the beaches, but apparently not occur- 

 ring alive above low water mark. 

 Emarginula fissura L. — Common from the 40 fms. Mena- 

 vawr dredgings, but never in a living state. 



E. rosea Bell. — With the above, but very much more scarce. 



J.C, iv., April, 1S85. 



