The 



Scottish Botanical Review 



No. 2] 1912 [April 



The Geological Relations of Stable and Migratory 

 Plant Formations. By C. B. Crampton, M.B., 

 CM., of H.M. Geological Survey. 



PAGE 



Part III. {contimied from p. 16). The Relation of Soils 



TO Climate and Physiography ... 57 



Part IV. The Stable Types of Vegetation in Britain 



{to be contimied) ...... 68 



Part III. The Relation of Soils to Climate 

 AND Physiography {continued). 



The chemical effect of lime on plant-association is not 

 merely a result of the outcrop of limestone rock at the surface. 

 The physiography or climate may, indeed, be such that it is 

 inappreciable, even where limestone forms the solid rock and 

 sub-soil ; and, conversely, the kind of plant-association may 

 indicate the presence of lime in the surface waters in places 

 remote from limestone or highly calcareous rocks. 



A few species have been shown to suffer in their metabolism 

 as a direct consequence of considerable quantities of lime in 

 the soil ; thus plants of the acid moorland and heath rarely 

 gain a footing except where lime is wanting or has been 

 leached from the surface (2). 



The presence of lime in the soil is, however, usually taken 

 as a gauge of fertility, and this is particularly the case in cold- 

 temperate humid regions where the surface-leaching of lime 

 so rapidly leads to soil-acidity and humus accumulation, with 



VOL. I. 5 



