BOOK REVIEWS. 



425 



BOOK EEVIEWS. 



"Diseases of Cultivated Plants and Trees." By George Massee, 

 P.L.S., V.M.H., 8vo., xiv. + 602 pp. (Duckworth, London, 1910.) 

 7s. 6d. net. 



More than ever before, the cultivator of plants of whatever kind 

 seeks to know the reasons of failure. He has learned that many of the 

 troubles to which his plants are heir are due to attacks upon them of 

 fungi or animals; and, though he is too proue, perhaps, to think that 

 all troubles must be laid at the door of these pests, yet the recognition 

 of the fact that disease is the effect of some definite cause or causey 

 is a great gain. Often the way is opened for disease-producing 

 organisms by bad (or probably it would be better to say improper) culti- 

 vation, arising from a lack of understanding of the physiology of plants. 

 The race for size and the desire to force plants beyond their capabili- 

 ties both assist in weakening their constitutions, with the result that 

 numerous diseases assail them to a markedly injurious extent. 



Many books have appeared dealing with diseases of plants brought 

 about by fungus or insect attacks, but the frequent additions to our 

 knowledge of the causes of disease soon render such books out of date, 

 and frequent revisions or entirely new works are required in order to be 

 abreast of the times. ' , " ' 



The author in 1899 published his Text-book of Plant Diseases," 

 and has wisely, now that it is out of print, rewritten the work entirely 

 upon a rather different plan and with the addition of much of the 

 work that has been done since his former volume was published. There 

 are two convenient ways of arranging a book on diseases due to para- 

 sites. One is to arrange it according to the nature of the plants 

 attacked — the method adopted by Dr. Cooke in " Fungoid Diseases 

 of Cultivated Plants," published by our Society; the other to arrange 

 it according to the nature of the organism causing the attack. The 

 author has adopted the latter method. It is one that certainly prevents 

 a great deal of repetition, and the disadvantages attaching to it are 

 entirely nullified when a good index is provided. 



The author has given a brief but good review of most of the common 

 physiological diseases and of some of those due to animal parasites, as 

 well as those due to the attacks of fungi and bacteria, the last occupy- 

 ing by far the greater portion of the book and constituting the part which 

 the author has made peculiarly his own. iVlmost all the diseases due 

 to these parasites claim attention in turn^ and a few are included that 

 are only of academic interest. Excellent accounts are given of such 

 well-known and troublesome diseases as "Black scab" or warty 



