TYPES OF BRITISH VEGETATION 139 



cally a new intensive method of study applied to our flora. The 

 editor leads off with a chapter on the Units of Vegetation, based 

 upon Dr. Moss's well-known paper. Then we have two chapters 

 on the conditions of vegetation in the British Isles as regards 

 physical characters and climate and soils, which, though referring, 

 of course, to the country at large, may remind some of us of what 

 was in 1869 the novel detail of the Introduction to Trimen and 

 Dyer's Flora of Middlesex. The soils of Scotland are treated by 

 Dr. W. G. Smith, whose brother Kobert may be termed the founder 

 of British ecological study, and those of Ireland by Professor 

 Grenville Cole, the rest of the part being by Mr. Tansley. The 

 bulk of the volume consists of descriptions of the fourteen plant- 

 formations recognized as British, with their sub-formations and 

 associations. Here we have Scottish Heaths, the Grass Moor 

 Association and Scottish Arctic-alpine Vegetation, with special 

 reference to Ben Lawers, described by Dr. Smith ; the Pennine 

 Eegion and the Sub-formation of the Older Limestones, by Dr. 

 Moss ; the Upland Moors of the Pennine Chain, also by him, in 

 conjunction with Mr. F. J. Lewis ; the British Freshwater Phyto- 

 plankton, by Professor G. S. West, indisputably our greatest 

 authority on the subject ; the Eiver-valleys of East Norfolk, by 

 Miss PalHs ; the Lowland Moors of Lonsdale, the Valley Moors of 

 the New Forest, and the Salt-marsh formation of the Hampshire 

 Coast, by Mr. W. M. Eankin, who is also part author with Mr. 

 Tansley of the chapter on '* the sub-formation of the Chalk "; and 

 the Maritime formations of Blakeney Harbour, in Norfolk — is 

 there not also a western Blakeney ? — by Professor F. W. Ohver. 

 When these interesting areas have been accounted for, there 

 remains a large number of associations which the editor has him- 

 self described. Under each association full Hsts of dominant 

 species are given, and the individual relations of their environ- 

 ment are discussed, while a special feature of the w^ork is the 

 tracing of the transitions from one formation to others. These 

 are represented by diagrams and an ingenious " genetic " table at 

 the end of the volume, while numerous sketch-maps elucidate the 

 topography. 



Valuable as is the text, however, its value is, in our opinion, 

 even surpassed by that of the illustrations. One cannot help 

 sometimes regretting that ecology, like golf, has loaded itself with 

 an enormous mass of terminology ; and in many books we see 

 photograph after photograph reproduced in which the individual 

 species are absolutely unrecognizable. It is difi&cult to see in 

 what degree such photographs add anything to the verbal de- 

 scriptions. It is, however, quite another matter with the majority 

 of the illustrations in this book. They are mostly landscapes, 

 not attempts to photograph plant-societies at close range : most 

 of them are extremely small, about four inches by three, and they 

 are process-blocks, so that a magnifying-glass brings out but httle 

 detail not visible to the naked eye. But, whatever size were the 

 original photographs, they have been so admirably selected, 

 lighted, and reproduced that almost all of them do tell their own 



