282 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLA.SGOW. 



though shallow loch. If that be the ease, then this 

 lisidhun 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 

 Sphcerium corneuin, Bythinia tentaculata, and Liiniicea 

 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 I 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 vtarginatay 

 Limax flavus, Zonites alJiarius var. viridula, Helix 

 aspersa var. scalariforine, H. arbustoruvi vars. 

 alpestris and flavescens, H. rufescens var. alba, H, 

 caperata var. major, H. rotundafa vars. pyramidalis 

 and alba, Pupa umhilicata vars. edentula and albina. 

 Vertigo pygmcea var. iDallida, 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. AVe 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 j30ssessing 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 



