BOOK REVIEWSj 



builder. Such being the case, readers of this fascinating volume will 

 share with its author the hope expressed in the concluding chapter that 

 in planning the new Delhi the Indian garden may be made to play an 

 important part. " If the palace at the new Delhi could form part of a 

 scheme with a great Imperial Indian Garden, with its symbolic divi- 

 sions, waterways, avenues, fountains and walls, Indian art would 

 receive a stimulus and Indian loyalty a lead which it would be im- 

 possible to overrate, although hard to believe in England, where the 

 gardens, beautiful as they are-, lack the practical use and deeper religious 

 significance of Indian garden-craft." 



" The Plant Societies of Chicago and Vicinity." By H. C. Cowles. 

 8vo., 76 pp. (University Press, Chicago, 1913.) 2s. net. 



Plant ecology is being studied enthusiastically, and many books are 

 appearing treating it in various ways. The word itself means Home- 

 study," and this may be pursued with various aspects. First, the 

 physical environm.ent or " home " of the plant may be the object ; 

 secondly, the plant's structure, internal and external, may be studied 

 to discover their physiological correlations with the various external 

 factors of the conditions of life ; thirdly, what plants are associated 

 together in any special kind of environment, as heathland, marsh, 

 woodland, alpine, maritime places, &c. ; lastly, the ecologist looks 

 to discover what evidence exists to show how the plants of any associa- 

 tion have acquired their special morphological characteristics, so as 

 to be in adaptation to them, i.e. their evolutionary history. 



The author regards the physiological aspect as one phase of 

 ecology ; but the second — the subject of the present treatise — is to 

 treat plant societies from a physiographical point of view. The 

 author discusses the three types of soil in the vicinity of Chicago, 

 viz. moraine, or boulder-clay deposit ; the Chicago plain ; and beach 

 or dune sands. Three types of vegetation correspond with the above : 

 the mesophytic upland forests of the morainic clays ; the hydro^ 

 phytic lakes and swamps, with the mesophytic prairies ; and the 

 xerophytic forests of the dunes and beaches. 



The keynote of the paper, the author says, is that each particular 

 topographic form has its own peculiar vegetation. 



The most important and new feature in the paper is the recognition 

 and description of the process of topographical changes, with the subse- 

 quent changes in the vegetation. 



These are effected by erosion, which causes the wearing down of 

 hills and the filling up of valleys, i.e. denudation and deposition. 

 The consequence is that certain plant societies disappear and are 

 replaced by others, better adapted to the new conditions. 



" One thing more must be recognized, and that is that environ- 

 mental influences are normally cumulative. A plant society is not a 

 product of present conditions alone, but the past is involved as well. 

 For example, a hydrophjrtic plant society may be seen growing in a 

 mesophytic soil." 



