Ki':\ii-:\\'s. 



HACTKRIOLOG^'. 



Microbiolnny for Aflriciiltiirnl ami Domestic Science 



Students. — ICditeii by Ciiakt.i:s K. M aksiiai.i.. 724 pages. 



128 illustrations and 1 coloured plate. Sj-in. X 5J-in. 



(J. & A. Churcliill. Price 10 6 net.) 



This is perhaps one of the most comprehensive books on 

 Bacteriology, nsing the term in its broadest sense, that is at 

 present available to English readers. Its prodnction has been 

 rendered possible as the result of the cooperation of a 

 number of American workers, each of whom is a .specialist in 

 the particular branch of the subject on which he writes. It 

 follows that the work covers a wide field, embracing as it 

 does, in addition to ordinary bacteriological methods and 

 technique, such branches as the microbiology of water, sewage 

 and soil, milk, plants and special industries. The culture, 

 morphology and physiology of micro-organisms is fully dealt 

 with, and in a manner that appeals particularly to those who 

 are called on to apply bacteriological methods to commercial 

 or industrial processes. 



Some apology is offered in the introduction for what is 

 evidently regarded as a somewhat serious objection to a work 

 which is the product of several hands, that there may be some 

 inevitable repetition. 



It must be admitted, however, that this fault, if it exists, is 

 not at all conspicuous, a tribute, it may be. to the care exercised 

 by the editor. The book may be recoiiunended to those who 

 wish to acquire a sound knowledge of the subject. It is none 

 the less valuable because it deals not only with laboratory 

 methods, such as may be found in nearly all works on 

 bacteriology, but is devoted especially to practical applica- 

 tions. T F I' 



BOTANY. 



Types of British Vegetation. — Edited by A. G. Tanslev, 



M.A., F.L.S. 416 pages. 36 plates and 21 text-figures. 



7^-in. X5-in. 



(The Cambridge University Press. Price 5/- net.) 



Plant Ecology is one of the most interesting branches of 

 Botany, and is also one of the youngest, its emergence as a 

 definite department of the study of plant-hfe being of cjuite 

 recent date. Ecology is more or less clo.sely related to plant- 

 geography on one hand, and to plant-physiology on the other. 

 The study of plant-geography in the wide sense goes back at 

 least as far as Humboldt's time, and is concerned with the 

 compilation of a list ("flora"! of the species growing in 

 larger or smaller areas and with the division of the earth's 

 surface into " floristic " areas according to the number of 

 species, genera, and families common to them. In a broad 

 sense, the object of physiology is the study of the external 

 factors of the environment in which the plant lives, and of the 

 activities and structural adaptations of the plant itself — ^the 

 former are the causes, and the latter the effects of these causes. 

 However, the scope and objects of Ecology are distinct 

 enough from those of floristic plant-geography as well as from 

 those of plant-physiology, and it may be defined as the 

 detailed and systematic study of plant-communities, in their 

 relations to each other. A plant-community is simply a 

 grouping of certain kinds of plants which are always found 

 associated together under definite conditions of life, or — to 

 <luote from the introduction to the book under review — it is 

 "a vegetation-unit regarded as an aggregation of species and 



indi\ iduals instead of as a division of the whole vegetation of 

 the region." 



This book, which contains numerous photographic illustra- 

 tions, well selected and admirably reproduced, in addition to 

 useful maps and diagrams, is the work of several authors, but 

 so skilfully has the difliculf task of the editor (also himself 

 largely a contributor) been done that the work presents all the 

 obvious advantages of this plan without any of the drawbacks 

 that it might have involved. The result is a work which not 

 only marks an epoch in the study of vegetation, but is also 

 absolutely indispensable to all students of the British flora 

 who wish their studies to extend beyond the mere collecting 

 and naming of plants. The book will prove of the greatest 

 value to the increasing number of field-botanists in this 

 country, to lovers of Nature, to students of scientific geography, 

 and to everyone interested in plant-life. It should certainly 

 be on the shelves of every school in which Nature-study is 

 taught, and should become an essential companion to the 

 " flora," field note-book and pocket-lens on botanical excur- 

 sions — fortunately, the form of the book is well adapted for 

 pocket use, though an India- paper edition would be welcome 

 when the book comes into general field use, as it undoubtedly 

 will. 



Following the editor's concise and clear introduction on the 

 units of vegetation and their relationships and classification, 

 the work falls into two parts. The first part (forty-seven 

 pages) deals with the physical characters, chmate, and soils of 

 the British Isles, and is mainly the work of the editor, though 

 Dr. W. G. Smith contributes the section on Scottish soils, and 

 Professor Grenville .\. J. Cole that on Irish soils. This part 

 of the book serves as a necessary preliminary to the det.ailed 

 study of the vegetation, and also forms in itself an admirably 

 terse, fresh, and interesting presentation of these physio- 

 graphical subjects, and as such is well worth careful perusal 

 by students and teachers of Geographj'. 



The second part, comprising the remainder of the book 

 (over three hundred and sixty pages), presents in detail the 

 existing vegetation of the British Isles, and is prefaced by the 

 editor's general account (Chapter I) of the distribution of the 

 vegetation. This is followed by fourteen chapters dealing 

 with the plant formation of clays and loams, the vegetation of 

 the coarser sands and sandstones, the heath formation, the 

 plant formation of the older siliceous soils, the vegetation of 

 calcareous soils, aquatic vegetation, the marsh formation, the 

 vegetation of peat and peaty soils, the vegetation of the river 

 valleys of East Norfolk, the moor formation (lowland moors, 

 upland moors of the Pennine Chain I, arctic-alpine vegetation, 

 and the vegetation ot the sea coast. In these chapters the editor 

 has had the collaboration of various botanists, who have made 

 special studies of certain areas, the chief contributors being 

 Miss Pallis, Dr. Smith, Dr. Moss, Professor Oliver, Dr. Lewis, 

 and Dr. W. M. Rankin. Throughout this second part of the 

 book one realises that the editor has, in addition to his own 

 contributions, performed with entire success the difticult task 

 of arranging and co-ordinating the various sections including 

 material from very many sources. 



As an example of the way in which the plant formations are 

 dealt with in this work, we may select one of the most familiar, 

 yet one of the most interesting of all — the heath formation. 

 The heathlands of Britain, and of north-west Europe as a 

 whole, are typically developed on poor sandy and gravelly 

 soils, where the climate is wetter than that which, to the 

 extreme east of Europe, gives rise to steppe ; on the other 

 hand, moorland is developed in regions of high rainfall, but 

 also on the sites of old lakes or where surface-water poor in 

 mineral salts has accumulated. The typical heath areas are 

 treeless, and the dominant plants are the dwarf shrubby mem- 

 bers of the "heather" family; the Mng (Calliina vulgaris) 

 is by far the most widespread and abundant species, and with 

 it are associated bell-heath {Erica cinerea^ and bilberry, and 



