Volume 4, Bulletins 44-60. (44) Effects of Certain Alkali Salts on Ammonification; (45) Soil Inoculation with Azotobacter; (46) Composition and Digestibility of Sudan Grass Hay; (47) Studies on the Clarification of Milk--II; (48) Milk As the Sole Diet of Ruminants; (49) Studies on the Crown Rust of Oats; (50) Effect of Crown Gall Upon a Young Apple Orchard; (51) Appetite as a Guide in Feeding Dairy Calves; (52) Studies on Abnormal Evaporated Milk; (53) Studies on Color in Swine; (54) Studies on Formation of Gas in Sweetened Condensed Milk; (55) Volatile Acid Production of Starters and of Organisms Isolated from Them; (56) Effect of Seasonal Conditions and Soil Treatments on Bacteria and Molds in Soil; (57) Relation of the Barberry to Stem Rust in Iowa; (58) Nitrification in Acid Soils; (59) Fungicidal Action of Formaldehyde; (60) Influence of Condition on Maintenance Requirements of Dairy Cattle