THE MOLLUSCA OF DORSETSHIRE. 61 
Weymouth Bay, numerous, W. Thompson ; near Sandsfoot 
Castle, under stones, where is also an albino variety, 
E. R. Sykes. 
Kimmeridge Bay (dredged), J. C. M.-P. 
Fossil: Coralline Crag ; Raised Beach, Portland, Prestwich. 
239. A. testudinalis (J7iil.) Patella testudinalis, iil. 
Lives on the under-side of stones at low-water and in the 
Laminarian zone. It is a northern species. 
Weymouth Bay, W. Thompson. 
PATELLIDA. 
PATELLA, L., 1757. 
240. P. vulgata, Z. PP. athletica, Bean. P. vulgata, 
var. depressa, Mont. 
Both forms generally distributed. 
Fossil : Raised Beach, Portland, Prestwich ; Blashenwell 
Quaternary tufaceous depcsit, J. C. M.-P. 
PATINA (Leach), Gray, 1847. 
241. P. pellucida (Z.) Helcion pellucidum (Z.) 
Patella pellucida, ZL. 
Two varieties of this limpet are met with on our coast. 
One is thin and transparent adorned with longitudinal 
lines of a bright blue colour; the other is thicker, 
stronger, and opaque, irregular in shape and with no 
iridescence in the inside. 
Inhabits the Laminarian zone, and is generally distributed 
round the coast. 
Portland, Pulteney. 
Weymouth, Pulteney. 
Studland Bay, shore, J. C. M.-P. 
Kimmeridge Bay, dredged, J. C. M.-P. 
Var, levis, Pennant. 
Weymouth, Damon. 
