68 
259. 
261. 
THE MOLLUSCA OF DORSETSHIRE. 
P. tigrinus, Miller. 
An extremely variable species. Some shells are perfectly 
smooth while others are ribbed (costata). 
Scarce on our coasts. 
Swanage, Miss Colson. 
Weymouth Bay, dredged, W. Thompson. 
Kimmeridge Bay, dredged, J. C. M.-P. 
Fossil : In the Coralline Red, and Mammaliferous Crags. 
. P. maximus (Z.) Ostrea maxima, L. 
Pulteney, p. 37, pl. 9, f. 3. 
Has a range of depth varying from 3 to 40 fathoms. 
“The sea between Portland and Purbeck has been long 
famous for the production of this species,” Pulteney. 
Weymouth Bay, a few have been trawled in the Bay and off 
Portland, but less abundantly than formerly, Z. R. Sykes. 
Kimmeridge Bay, dredged in deep water, J. C. M.-P. 
Between South Haven and Studland, after storms and high 
seas, valves may be seen strewn as high as the sand- 
dunes, J. C. M.-P. 
Fossil : Coralline Crag. 
LIMA, Bruguiére, 1792. 
The Limas move backwards. 
L. Loscombii, G. B. Sowerby. 
Portland, dredged, 15 fathoms, McAndrew and E. Forbes. 
Weymouth, Damon. 
Kimmeridge Bay, dredged, 10 fathoms, J. C. M.-P. 
Worbarrow Bay, dredged, J. C. M.-P. 
Fossil : Coralline Crag. 
MYTILIDAS. 
MYTILUS, Z., 1758. 
Several often found together attached by the byssus to 
stones and often to floating objects. 
. M. edulis, Z. 
Pulteney, p. 39, pl. 12, f. 5. 
Generally distributed round the coast, and in estuaries. 
. pellucida, Penn. Weymouth, Z. R. Sykes. 
Fossil: Coralline Crag. Raised beach, Portland, Prestwich. 
