THE MOLILUSCA OF DORSETSHIRE. 57 
GIBBULA, Risso, 1826. 
222. G. magus (Z.) Trochus magus, L. 
2 
2 
24. 
Pulteney, p. 48, pl. 16, f. 1, 2. 
One of the most beautiful of the Trochidw, variegated 
with rosy tints on a white ground. It lives at various 
depths. 
Weymouth Bay, dredged, W. Thompson, E. R. Sykes. 
Between Studland and South Haven, cast up on the shore, 
J.C. M.-P. 
Poole Harbour, shore, J. C. M.-P. 
Kimmeridge Lay, dredged (alive) at various depths, 
J.C. M.-P. 
. G. cineraria (Z.) Trochus lineatus, Pulé. 
Pulteney, p. 48, pl. 16, f. 11, 12. 
Around our coasts on stones, and sea-weed at low-water-mark, 
abundant in the Laminarian zone. 
Generally distributed. 
Fossil : Red Crag. 
G. umbilicata (Mont.) Trochus umbilicatus (Jfont.) 
This Littoral shell, though abundant wherever it occurs, is 
confined to the Southern and Western coasts. 
Pulteney, p. 48, pl. 16, f. 7, 8. 
Generally distributed. 
Fossil : Raised Beach, Portland, Prestwich. 
. G. tumida (Mont.) Trochus tumidus, Mont. 
Pulteney, p. 48, pl. 16, f. 9, 10. 
An abundant shell on our coasts, usually found in the 
Coralline zone. 
Weymouth, Bryer. 
Weymouth Bay, dredged, W, Thompson. 
Shore, between Studland and South Haven (dead), Carleton 
Green. 
Kimmeridge Bay, dredged at various depths, abundant, 
J.C. M.-P. 
Fossil: Red and Mammaliferous Crags. 
