iowa. 45 
24. Determination of amino acids and nitrates in soils: Amino acids, ammonia and nitrates in manured 
andlimed soil. By R. S. Potter and R. S. Snyder. July, 1915. 
25. Bacterial activities and crop production. By P. E. Brown. July, 1915. 
26. Studies on the determination of sulfur as barium sulfate. By P. L. Blumenthal and S. C. Guernsey. 
Sept., 1915. 
27. Studies on the formation of gas in milk. By B. W. Hammer. Jan., 1916. 
28. Studies on the clarification of milk. By B. W. Hammer. Jan., 1916. 
29. Studies on the numbers of bacteria in milk showing various changes. By B. W. Hammer and R. H. 
Hix. Jan., 1916. 
30. Inheritance of color and horns in blue gray cattle. By Orren Lloyd-Jones and J. M. Evvard. Jan., 
1916. 
31. Studies on the creaming ability of milk. By B. W. Hammer. July, 1916. 
32. Estimation of calcium in ash of forage plants and animal carcasses. By S. B. Kuzirian. Mar., 1916. 
33. Studies on a fusarium disease of corn and sorghum. (Preliminary.) By L. H. Pammel, Charlotte 
M. King, and J. L. Seal. Mar., 1916. 
34. Studies in sulfofication. By P. E. Brown and H. W. Johnson. July, 1916. 
35. Effect of some manganese salts on ammonification and nitrification. By P. E. Brown and G. A. 
Minges. July, 1916. 
36. Influence of humus forming materials of different nitrogen-carbon ratios on bacterial activities. By 
P. E. Brown and F. E. Allison. July, 1916. 
37. Environmental influences on nectar secretion. By L. A. Kenoyer. Nov., 1916. 
38. Fishiness in evaporated milk. By B. W. Hammer. Jan., 1917. 
39. Carbon dioxide production in soils and carbon and nitrogen changes in soils variously treated. By 
R. S. Potter and R. S. Snyder. Feb., 1916 [i. e. 1917]. 
40. The relative influence of microorganisms and plant enzyms on corn silage fermentation. By A. B. 
Lamb. Mar., 1917. 
41. A rapid volumetric method for approximate estimation of chlorine in milk. By B. W. Hammer and 
D. E. Bailey. June, 1917. 
42. The occurrence and significance of mannitol in silage. By A.W. Doxand G. P. Plaisance. Dec, 1917. 
43. Effect of sulfur and manure on availability of rock phosphate in soil. By P. E. Brown and A. R. 
Gwinn. Dec, 1917. 
44. Effects of certain alkali salts on ammonification. By P. E. Brown and D. R. Johnson. Jan., 1918. 
45. Soil inoculation with aztobacter. By Paul Emerson, Feb., 1918. 
46. Composition and digestibilitv of Sudan grass hay. By W. G. Gaessler and A. C. McCandlish. Feb., 
1918. 
47. Studies on the clarification of milk, II. By B. W. Hammer and A.J, Hauser. Mar., 1918. 
48. Milk as the sole diet of ruminants. By A. C. McCandlish. Aug., 1918. 
49. Studies on the crown rust of oats. By I. E. Melhus and L. W. Durrell. Feb., 1919. 
50. The effect of crown gall upon a young apple orchard. By Laurenz Greene and I: E. Melhus. Mar., 
1919. 
51. Appetite as a guide in feeding dairy calves. By A. C. McCandlish, Aug., 1919. 
52. Studies on abnormal evaporated milk. By B. W. Hammer. Aug., 1919. 
53. Studies on color in swine: I, The hereditary relationship of the black of the Hampshire and the red 
of the Duroc- Jersey. By Orren Lloyd- Jones and J. M. Evvard. Nov., 1919. 
54. Studies on formation of gas m sweetened condensed milk. By B. W. Hammer. Sept., 1919. 
55. The volatile acid production of starters and of organisms isolated from them. ByB. VV. Hammerand 
D.E.Bailey. Sept., 1919. 
56. Effect of seasonal conditions and soil treatment on bacteria and molds in soil. By P. E. Brown and 
W. V. Halversen. Dec, 1919. 
57. Relation of the barberry to stem rust in Iowa. By I. E. Melhus, L. W. Durrell, and R. S.Kirby. 
Jan., 1920. 
58. Nitrification in acid soils. By R. E. Stephenson. Aug., 1920. 
59. The fungicidal action of formaldehyde. By I. E. Melhus, J. C. Oilmen, and J. B. Kendrick. Aug., 
1920. 
60. Influence of condition on the maintenance requirements of dairy cattle. By A. C. McCandlish and 
W. G. Gaessler. Sept., 1920. 
61. A study of lactose-fermenting yeasts present in "yeasty" cream. By B. W. Hammer and W. A. 
Cordes. Sept., 1920. 
62. Comparative resistance of varieties of oats to crown and stem rusts. By L. W. Durrell and J. H. 
Parker. Oct., 1920. 
63. Volatile acid production of <S. lacticus and the organisms associated with it in starters. By B. W. 
Hammer. Oct., 1920. 
64. A study of brown glass milk bottles, with special reference to their use in preventing abnormal flavors 
due to fight. By B. W. Hammer and W. A. Cordes. Nov., 1920. 
65. The type of lactic acid produced by starters and by the organisms isolated from them. By B. W. 
Hammer. Nov., 1920. 
SOIL SURVEY REPORTS. 
1. Bremer County soils. By W. H. Stevenson, P. E. Brown, and F. B. Howe. Jan., 1917. 
2. Pottawattamie County soils. By W. H. Stevenson, P. E. Brown, H. P. Hanson, and H. W. Reid. 
Jan., 1918. 
3. Muscatine County. By W. H, Stevenson, P. E. Brown, and H. W. Johnson. Apr., 1918. 
4. Webster County soils. By W. H. Stevenson, P. E. Brown, F. B. Howe, and G. E. Corson. July, 
1918. 
5. Lee County. By W. H. Stevenson, P. E. Brown, M. E. Sar, and G. E. Corson. Sept., 1918. 
6. Sioux County. By W. H. Stevenson, P. E. Brown, G. E. Corson, and W. C. Bean. Nov., 1918. 
7. Van Buren County soils. By W. H. Stevenson, P. E. Brown, G. E. Corson, and H. W. Reid. Dec, 
1918. 
8. Clinton County. By W. H. Stevenson, G. E. Corson, and F. B. Howe. Dec, 1918. 
9. Scott County soils. By W. H. Stevenson, P. E. Brown, G. E. Corson, and Knute Espe. Jan., 1919. 
10. Ringgold County. By W. H. Stevenson, P. E. Brown, G. E. Corson, F. B. Howe, and M. E. Olson. 
Feb., 1919. 
11. Mitchell County. By W. H. Stevenson, P. E. Brown, G. E. Corson, Knute Espe, and M. E. Olson. 
Feb., 1919. 
12. Clay County. By W. H. Stevenson, P. E. Brown, G. E. Corson, T. H. Benton, and M. E. Olson, 
May, 1919. 
13. Montgomery County. By W. H. Stevenson, P. E. Brown, G. E. Corson, M. E. Olson, and L. L. 
Rhodes. July, 1920. 
14. Black Hawk County. By W. H. Stevenson, P. E. Brown, G. E. Corson, and H. J. Harper. July, 
1920. 
