122 The Mollusca of Cambridgeshire 



Valloni pnkhella and F costata, for which records also the 

 writer is indebted to the Rev. A. H. Cooke. Damp spots in 

 this neighbourhood contain Succinea putris. In the woods 

 round Grantch ester Helicigona arbustorum is common, as well 

 as along the course of the Cam above and below Cambridge. 

 This species is fond of the willows and it is not unusual 

 to find Helix nemoralis at the same time. During the Long 

 Vacation of 1892 on a day when the river was in flood the 

 writer found the raised foot-path across the meadows from 

 Waterbeach Station to Bottisham Lock crowded with indi- 

 viduals of these two species, which had found refuge thereon 

 from the water covering the grassland on either side. Of 639 

 specimens of Helicigona arbustorum picked up haphazard from 

 80 yards of the foot-path 465 were adults, and of these 15 

 were without any trace of the band which is typical of this 

 species. In practically all the rest the band was well-marked 

 for several whorls, so that the variation was markedly dis- 

 continuous. Of 261 adult examples of Helix nemoralis taken 

 from the same spot 21 were without bands, and were mostly 

 brownish in colour, a few being orange or yellow. The 

 banded specimens forming the majority were of most of the 

 usual colours, while the banding varied so greatly as to defy 

 any summary expression, as is so often the case in this species. 



In the contiguous districts of Harston, Hauxton and 

 Hoffer's Bridge to the south of Cambridge several of the 

 less common species have been found, for instance, Vitrea 

 rogersi, V.radiatula, Punctum pygmaeum, Caecilioides acicula, 

 Vertigo antivertigo and F. pygmaea. Arion intermedius 

 occurs at Whittlesford to the east of the above places. 



Passing eastward from the lower lands to the Chalk 

 of the Gogmagog Hills and their approaches we find some of 

 the Helicidae very numerous. Helicella virgata is plentiful 

 in both the type forms and several of the more or less recog- 

 nised varieties. H. itala and H. cantiana are also common, 

 while Ena obscura and Cochlicopa lubrica are not rare. 

 Several of the less common species have been found in the 



