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sidered LimncEa glutinosa, Miill., which occurs in two other 

 places, and in the marshes near Reculvers is rather common. 

 Almost without exception the shells which are found through 

 Putney, Barnes, and Kew occur again here, as PL corneus, L., 

 various species of Limncea, Pisidiimi roseum, Scholtz., etc. 

 It is curious that several shells in this district have white 

 varieties, as though there were some peculiarity in the place 

 which tended to produce albinism. As examples of this 

 Planorbis corneiLS, L., Limncza pahistris, Miill., and Physa 

 fontmalis, L., have each a white var. occurring in the 

 marshes. 



North Downs Division. — This division is the broad belt of 

 chalk downs extending from East Kent away through Surrey 

 and Hampshire, ending beyond the district with which we 

 are now dealing on the borders of Wiltshire. As might be 

 expected we have here a considerable change in the fauna, and 

 we find a number of those shells which in the south of England 

 at least are always associated with the chalk downs. In 

 walking through Surrey or Kent no one can fail to be struck 

 by the change in mollusca on passing from the tertiary clay 

 or sand to the cretaceous, and it is impossible to believe, as I 

 said before, that this can be merely attributable to accident. 

 Among the most noticeable shells are H. po7natia, L., which 

 occurs at intervals, and in a few places, as Dorking, Cater- 

 ham, and Reigate, etc., is extremely common. H. lapicida, 

 L., an uncommon species, and other such shells as Helix 

 virgata, Da Cos., H. ericetorimi, Miill., H. caperata, Mont, and 

 Cyclostoma elegans, Miill., Claiisilia laminata, Mont., and C. 

 rolphii, Gray., and Coch. tridens, Pult. None of these shells 

 I think, occur anywhere in the district north of these downs. 

 At Caterham occurs a very beautiful yellow variety of H. 

 aspersa, Miill. ; it is found by the side of the road feeding on 

 Clematis vitalba ; and white varieties of H. rotundata, Miill., 

 and Hyalina nitidulus, Drap., I have taken at Orpington, 

 but they are far from common. 



On the Kentish coast is found one of the most rare, if not 

 the rarest British shell, Acme lineata, Drap., a white variety 

 of which has been taken at Folkestone. 



Testacella is found rather commonly at Croydon and Nor- 

 bury. My last authority for this is our gardener, who is very 



