228 Proceedings of the Royal Physical Society. 
CLass GASTEROPODA. 
Order CYCLOBRANCHIATA. 
Family CHITONID. 
Chiton, Chiton sp. 
Linne. 
A single plate of a chiton sp.? was obtained from the 
material. 
Order PECTINIBRANCHIATA. 
Family PATELLIDA (PATELLAD/). 
Patella, Patella vulgata, Linne. 
Lister. 
Patella vulgata, Linn., Syst. Nat., p. 1258. 
F. and H., vol. ii., p. 421, pl. lxi., figs. 5 and 6. 
Jeff., loc. cit., vol. iii., p. 236; vol. v., pl lvil, faa 
Rare. This species appears to be of frequent occurrence in 
raised beaches and estuarine clays, and is recorded as having 
been obtained from various places in Scotland. 
It is found living on all the rocky coasts of the British 
Islands. 
Helcion, Helcion pellucidum (Linne). 
De Montfort. 
Patella pellucida, Linn., Syst. Nat., p. 1260. 
= F. aid Ee vol. ii., p. 429, pl. lxi., figs. 3 and 4. 
elon petiueiium, Jeff, loc. cit., aR; iii., p. 242; vol. v., pl. lviii., fig. 1. 
Frequent. As a fossil this species has been found at Largo, 
Banff, the Clyde beds at Garvel Park, near Greenock, and at 
other places in Scotland ; it has also been obtained in Ireland. 
As a living species it is of frequent occurrence all round 
our coasts, and is usually found on the fronds of Laminaria. 
Tectura, Tectura virginea (Muller). 
Cuvier. 
Patella virginea, Muller, Prodr. Zool. Dan., p. 237. 
Acmeea virginea, F, and H., vol. ii., p. 437, pl. lxi., figs. 1 and 2. 
Tectura virginea, Jeff., loc. cit., vol. iii., p. 248; vol. v., pl. lxiii., fig. 4 
Rare. This species as a fossil appears to be generally 
distributed ; in its living state it is equally common. 
