138 PLANT PHYSIOLOGY 
collect and examine as many different types of plant diseases 
as he can find, for the mere ability to recognize diseased condi- 
tions is of great value. 
REFERENCE BOOKS 
C. R. Barnes, Physiology (in Text-book of Botany by Coulter, 
Barnes & Cowles), Chicago, 1910. 
L. Jost, Lectures on Plant Physiology (Engl. Ed., Oxford, 1909). 
W. Prerrer, The Physiology of Plants (Engl. Ed., Oxford, 1900- 
1906). 
B. M. Duaa@ar, Plant Physiology, 1911, New York. 
R. J. Poot , Suggestions for Experiments in Plant Physiology, 
1914, Lincoln. 
For the chemical aspects of this chapter and especially for the 
- following chapter the following books are useful. 
Haas AND Hi 1, Introduction to the chemistry of Plant Products 
1913, New York. 
F. Czarexk, Biochemie der Pflanzen, 1913, Jena. 
