202 Proceedings of the Royal Physical Society. 
Rissoa semistriata (Montagu). 
Turbo semistriatus, Mont., Test. Brit. Suppl., p. 136. 
Lissoa semistriata, F. and H., vol. iii., p. 117, pl. lxxx., figs. 4-7. 
Jeff., Joc. cit., vol. iv., p. 46; vol. v., pl. Ixxviii., 
fig. 8. 
39 39 
Not common. With the exception of Rissoa semistriata, 
all the Zzssow here tabulated have been recorded from the 
Clyde beds. Among the Zissow recorded by Mr Alfred 
Bell in his paper “On the Marine Accumulations at Cockle- 
mill Burn in Largo Bay, Fifeshire,’! as far as we can make 
out Lissoa striata and Rissoa parva are the only species 
that have representatives in the Fillyside raised beach. 
All these Fissow are found living on the coasts of these 
islands. 
Hydrobia, Hydrobia ulve (Pennant). 
Hartmann. 
Turbo ulve, Penn., Brit. Zool., vol. iv., p. 132, t. Ixxxvi., fig. 120. 
Rissoa ulve, F. and H., vol. iii., p. 141, pl. lxxxi., figs. 4, 5, 8, 9; 
pl. Ixxxvii., figs. 2-8. 
Hydrobia ulve, Jeff., loc. cit., vol. iv., p. 52; vol. v., pl. lxix., fig. 1. 
Rare. This species has been recorded as fossil from 
Largo; the Clyde beds at Dalmuir and Paisley ; from the 
estuarine clays of Belfast and Strangford Lough; and from 
the Norwich and Coralline Crags. 
Hydrobia ulve is found living in all the tidal rivers, ee 
and inlets, covering the mud flats and oozy sand in countless 
numbers. 
Family SKENEIDZ (SKENEADZ). 
Skenea, Skenea planorbis (Fabricius). 
Fleming. 
Turbo planorbis, Fabr., Faun. Greenl., p. 394. 
Skenea planorbis, F. and H., vol. iii., p. 156, pl. lxxiv., figs. 1-8. 
Jeff., loc,. cit., vol..iv., p. 65; vol. v.,-pl. xa ieee 
99 93 
Frequent. As a fossil this species has been found at Largo, 
and in most of the Post-Tertiary beds of the west coast. 
1 Proc. Roy. Phys. Soc., vol. x., part ii., p. 290, 
