STUDIES IN THE PHYSIOLOGY OF THE FUNGI. 
XVII. THE GROWTH оғ CERTAIN Woop-DEsTROYING FUNGI 
IN RELATION TO THE Н-Іом CONCENTRATION 
OF THE MEDIA! 
F. S. WOLPERT 
Formerly Rufus J. Lackland Fellow in the Henry Shaw School of Botany of 
Washington University 
Chairman of the Botany Department, The Principia, St. Louis 
| INTRODUCTION 
That wood-destroying fungi grow more favorably upon sub- 
stances acid in reaction has been appreciated by many students 
who have given attention to the biology of these organisms. 
Investigations in this field have received а marked impetus from 
the recently perfected methods for determining the hydrogen-ion 
concentration of solutions. Webb (19, '21) has given many 
interesting data upon the effect of hydrogen-ion concentration 
upon spore germination, while other investigators from this 
` laboratory and those from other laboratories have worked upon 
the relationships of hydrogen-ion concentration of the medium 
to the mycelial growth of some of the Agaricales. 
However, since this order of the fungi contains such a large 
number of wood-destroying species, and because increased 
knowledge of their biology leads to better methods of combating 
their spread and ravages, through improved methods of preserva- 
tion from a practical as well as from an academic standpoint, 
it seems advisable to make a more detailed study of the following 
questions: What hydrogen-ion concentration will inhibit mycelial 
growth of these fungi? How do these fungi react to hydrogen- 
ion concentration in different types of media and at different 
temperatures? Is growth always inhibited by an alkaline solu- 
! An investigation carried out at the Missouri Botanical Garden in the Graduate 
Laboratory of the Henry Shaw School of Botany of Washington University, and 
submitted as а thesis in partial fulfillment of the requirements for the degree of 
doctor of philosophy in the Henry Shaw School of Botany of Washington University. 
Ан». Мо. Вот. Garp., Vor. 11, 1924 (43) 
