258 PROCEEDINGS OP THE MALACOLOGICAL SOCIETY. 



with the introduction of Bronze into England, but the evidence is 

 against this. Grimes Graves (Norfolk), Blashenwell (Dorset), as 

 already noted, and the Neolithic grave at Cuxton, Kent {Proc. 

 Malac. Soc. Lond., vol. viii, 1909, pp. 375-6) are all Neolithic, and 

 certainly not late Neolithic. The mollusca (as yet undescribed) 

 obtained from the recent extension of the new Albert Docks are of 

 this age, for they occurred between the two forest growths, and here 

 again the only archaeological objects noted were flint flakes and 

 implements. As to the climate one can only say with safety that 

 it was much damper than the present. 



Stage 2. The Upper Forest Growth. This is a return to a " con- 

 tinental type " of climate, but not so pronounced as in Stage 6. 

 On archaeological evidence this can be shown to be of Bronze Age 

 about 1500 B.C., and the recent exploration of a Bronze Age tumulus 

 at Micheldever, Hampshire, has yielded strong confirmatory evidence 

 from the mollusca, for they are all well developed. 



Of the succeeding damp stage No. 1 we have no evidence. It 

 was certainly not so extreme as the preceding damp stage, and it 

 may be that it was confined to Scotland. There is, however, slight 

 evidence that during the Roman occupation of this country the 

 climate was slightly warmer than at present, for in Roman deposits 

 the mollusca are nearly always slightly larger than those now living 

 near the sites. 



We thus see that there is a marked agreement between the con- 

 clusions derived from the mollusca and those deduced from the 

 peat mosses, and we can, I think, conclude that the scheme of 

 Professor Lewis is in the main correct. 



It is interesting to note that there are but few abnormalities in 

 the Holocene mollusca, although an enormous amount of material 

 has passed through my hands. Only one sinistral shell has been 

 found, an example of Arianta arhustorum (Linn.), at Uxbridge, 

 Middlesex, whilst a few scalariform Limnseae and Planorbes have 

 occurred in the Lea Valley deposits. The Limnaeae at Perranzabuloe, 

 Cornwall, were, however, nearly all abnormal, and this was certainly 

 the result of the. conditions in which they jived. I would suggest 

 that in this case the lake was subject to slight incursions of the sea. 



I have endeavoured to show that the formerly ignored or despised 

 and maltreated Holocene mollusca are of great importance in several 

 lines of research, and that they can be used as evidence in solving 

 many problems, and I would take this opportunity of thanking those 

 numerous friends by whose kind assistance this has been possible. 

 In pioneer work of this character, based, as I have already noted, on 

 imperfect knowledge, temporary mistakes are bound to occur, to be 

 rectified as our learning increases. I have had to make bricks with 

 but little straw. Whether they will be lasting or not the future will 

 tell, but this is certain — that the work has not only given me interest 

 and pleasure, but has produced friendships which will last to the 

 end of the chapter. 



