UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 1380 
Washington, D. C. 
Issued May, 1926 
A PATHOLOGICAL SURVEY OF THE 
PARA RUBBER TREE (HEVEA BRASILIENSIS) 
IN THE AMAZON VALLEY 
JAMES R. WEIR, Pathologist of the Expedition of the United States Departments of Agriculture 
and Commerce to Investigate the Sources of Crude Rubber in the Amazon Valley 
and Pathologist in Charge of Pathological Collections 
Bureau of Plant Industry 
CONTENTS 
Page 
Preface 1 
General Pathological Conditions and Sanitation 2 
Special Diseases 6 
Physiological Disturbances and Abnormalities 56 
Prepared Robber 77 
Fungi Reported on Hevea 79 
Mistletoes on Hevea 94 
Algae on Hevea „ . 96 
Bibliography 97 
WASHINGTON 
GOVERNMENT PRINTING OFFICE 
1926 
