REVIEWS 505 



on most works covering the same ground. Among its other good qualities are 

 the extremely numerous, and for the most part good illustrations, the introduction 

 of the names and portraits of botanists who have built up the subject, and, not 

 least, its very reasonable price. 



Although it is the plant as a living organism which is the underlying theme of 

 the author's presentation of botany, it is interesting, and it will reassure the 

 morphologist, that Dr. Gager, himself a plant physiologist, devotes upwards of 

 450 pages, or nearly three-quarters of the book, to the structures and life histories 

 of the various " types," while in the selection of these types there is nothing 

 revolutionary, although in some cases, as in that of the fern, it is not any particular 

 species which is described, but rather a description of the structure and life history 

 of ferns as a group, with reference to numerous different species. And in all that 

 part of the book dealing with structures and life histories, the mode of living of the 

 plant is adequately dealt with, and not its structure alone. 



The author holds that an introductory course should not be "presented on the 

 supposition that its main purpose is to pave the way for more advanced courses," 

 but "to introduce the pupil to a new realm of thought" . . . "not to make the 

 subject simple — to remove all difficulties — but to make it really interesting." 

 With these views we must agree, and we must also agree that Dr. Gager has put 

 them into practice in his Fundamentals of Botany. 



W. S. 

 / 



Soil Biology Laboratory Manual. By A. L. Whiting, Ph.D. [Pp. x + 143, 

 with numerous schedules.] (New York: John Wiley & Sons; London: 

 Chapman & Hall, Ltd., 1917. Price $1.25 net, or 6s.) 



In his preface the author states that " Soil Biology treats of the micro-organisms 

 which inhabit soils in their relation to soil fertility, crop production, and permanent 

 agriculture." But in our opinion, to limit the use of the term biology simply to 

 organisms of microscopic size is an unjustifiable circumscription of the word 

 biology. To take just one example, any work on " Soil Biology " that takes no 

 account of the part played by earthworms in the formation of moulds, aeration, 

 drainage, etc., is obviously not fulfilling its title. In the present case the volume 

 would have had its contents more accurately indicated had it been termed "The 

 Micro-organisms of the Soil," or some such title suggestive of its more limited 

 scope. Apart from this the book is an arrangement of practical exercises well 

 collected and destined to give the student not only a knowledge of protozoology, 

 bacteriology, and mycology in as far as they affect soil, but also a series of useful 

 biochemical tests by which their presence may be detected and their work esti- 

 mated. It should prove valuable in any institution in which courses in agriculture 

 or horticulture are given, and the explanations provided are sufficiently clear in 

 most cases to enable a student of average ability to carry out the experiments for 



himself. 



C. H. O'D. 



Ail Outline of the History of Phytopathology. By Herbert Hice 

 Whetzel, Professor of Plant Pathology at 'Cornell University, Ithaca, 

 New York. [Pp. 130, with 22 portraits.] (Philadelphia and London : 

 W. B. Saunders Company, 1918. Price 7s. 6d. net.) 



This little book does not pretend to be more than an account in outline of the 

 most important features in the history of the developmept of plant pathology ; 

 it makes no attempt at a complete history of the science. 



33 



