152 



and a certain amount of revision. It is a pleasure to note that 

 the author has retained the original plan of the book which 

 makes it a work on botany rather than a mere compendium of 

 diseases. It thus takes on both a physiological and an ecological 

 interest. The author is evidently not greatly concerned with 

 genetics, at any rate he gives scant attention to the subject of 

 disease-resistant strains. Like others who are engaged in "prac- 

 tical" work he has not been able to refrain from introducing 

 some "Farmers'-Bulletin" illustrations such as Fig. 2 "Class in 

 Plant Pathology at the State College of Washington." This and 

 other figures could be omitted to advantage. 



A convenient division of the book is made, into four sections: 

 I, Introduction and symptoms of disease; II, Non-parasitic dis- 

 eases; III, Virus and related diseases; IV, Parasitic diseases. In 

 the last-named section there are chapters on diseases caused by 

 bacteria, slime molds, fungi, parasitic seed plants, and nema- 

 todes. Most of the diseases are discussed as follows: history, 

 geographical distribution, symptoms, economic importance, 

 etiology, host relations, prevention and control. 



Every botanist needs to know something about plant dis- 

 eases, and here is a very satisfactory presentation of the sub- 

 ject. The book in its present form should prove even more use- 

 ful than the first edition, which has been a standard reference 

 work for seven years. 



Francis Ram ale y 



