TRANSCRIBER NOTES: Words in italics are indicated with an underscore (_) at the begining and end. Words in bold are indicated with an equal sign (=) at the begining and end. Subscripts contained in chemical notations are indicated as _{ }. The table on page 32 has been modified to fit by the use of keys to replace some of the information. U. S. DEPARTMENT OF AGRICULTURE. BUREAU OF PLANT INDUSTRY--BULLETIN NO. 129. B. T. GALLOWAY, _Chief of Bureau_. BARIUM, A CAUSE OF THE LOCO-WEED DISEASE. BY ALBERT C. CRAWFORD, PHARMACOLOGIST, POISONOUS-PLANT INVESTIGATIONS. ISSUED AUGUST 22, 1908. [Illustration] WASHINGTON: GOVERNMENT PRINTING OFFICE. 1908. BUREAU OF PLANT INDUSTRY. _Physiologist and Pathologist, and Chief of Bureau_, Beverly T. Galloway. _Physiologist and Pathologist, and Assistant Chief of Bureau_, Albert F. Woods. _Laboratory of Plant Pathology_, Erwin F. Smith, Pathologist in Charge. _Investigations of Diseases of Fruits_, Merton B. Waite, Pathologist in Charge. _Laboratory of Forest Pathology_, Haven Metcalf, Pathologist in Charge. _Cotton and Truck Diseases and Plant Disease Survey_, William A. Orton, Pathologist in Charge. _Plant Life History Investigations_, Walter T. Swingle, Physiologist in Charge. _Cotton Breeding Investigations_, Archibald D. Shamel and Daniel N. Shoemaker, Physiologists in Charge. _Tobacco Investigations_, Archibald D. Shamel, Wightman W. Garner, and Ernest H. Mathewson, in Charge. _Corn Investigations_, Charles P. Hartley, Physiologist in Charge. _Alkali and Drought Resistant Plant Breeding Investigations_, Thomas H. Kearney, Physiologist in Charge. _Soil Bacteriology and Water Purification Investigations_, Karl F. Kellerman, Physiologist in Charge. _Bionomic Investigations of Tropical and Subtropical Plants_, Orator F. Cook, Bionomist in Charge. _Drug and Poisonous Plant Investigations and Tea Culture Investigations_, Rodney H. True, Physiologist in Charge. _Physical Laboratory_, Lyman J. Briggs, Physicist in Charge. _Crop Technology and Fiber Plant Investigations_, Nathan A. Cobb, Crop Technologist in Charge. _Taxonomic and Range Investigations_, Frederick V. Coville, Botanist in Charge. _Farm Management Investigations_, William J. Spillman, Agriculturist in Charge. _Grain Investigations_, Mark Alfred Carleton, Cerealist in Charge. _Arlington Experimental Farm_, Lee C. Corbett, Horticulturist in Charge. _Vegetable Testing Gardens_, William W. Tracy, sr., Superintendent. _Sugar-Beet Investigations_, Charles O. Townsend, Pathologist in Charge. _Western Agricultural Extension Investigations_, Carl S. Scofield, Agriculturist in Charge. _Dry-Land Agriculture Investigations_, E. Channing Chilcott, Agriculturist in Charge.