982 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 
though shallow loch. If that be the case, then this 
Fisidium and its neighbours in these pools may be 
the descendants of ancestors dating back to a 
“remote and venerable antiquity,” and not com- 
paratively recent introductions, as some species un- 
doubtedly are. A year or two ago I introduced 
Spherium corneum, Bythinia tentaculata, and Limnca 
stagnalis, into a dam near Greenock; but by the 
following year they all appeared to have died out, 
as no trace could be seen of any of them. Though 
aquatic species be so few about Greenock and the 
neighbouring districts, there are a good many 
terrestrial molluscs; and my son and Ii have been 
able to add not only new stations for some of the 
rarer species recorded in the list of 1876, but also a 
few species and varieties not included therein. The 
species and varieties added are Amalia marginata, 
Limax flavus, Zonites alliarius var. viridula, Helix 
aspersa var. scalariforme, H. arbustorum vars. 
alpestris and flavescens, H. rufescens var. alba, H. 
caperata var. major, H. rotundata vars. pyramidalis 
and alba, Pupa umbilicata vars. edentula and albina, 
Vertigo pygmea var. pallida, V. substriata, and 
Clausilia rugosa monst. decollatum (?). This form of 
Clausilia rugosa was found on a wall by the side of 
the Inverkip road about four miles from Greenock. 
My son and I picked up a good number of living 
specimens; but these were not all exactly alike, 
some having lost more and some less of the apical 
end of the shell. We could not arrive at any con- 
clusion as to the reason why the shells were thus 
broken; but whatever may have been the cause the 
animals appeared to be uninjured, as they were as 
lively as any of those possessing whole shells. We 
also got a specimen which either had had its shell 
broken and the broken part attached again—but in 
an awkward position, being nearly at right angles— 
or else the end was in process of being broken off. 
In all the damaged specimens found, we did not see 
one that had the broken end soldered up, as is 
5 
