REFERENCES 34! 



21. MUNTZ : Comptes Rendus de PAcademie des Sciences, CX 



(1890). 



22. STOKER : Agriculture, Vol. I. 



23. DYER : Journal of the Chemical Society, March, 1894. 



24. Goss : Association of Official Agricultural Chemists Report, 



1896; also SNYDER : Minnesota Experiment Station Bulletin 

 No. 102. 



25. PETER : Association of Official Agricultural Chemists Report, 



1895 ; also Journal Analytical and Applied Chemistry, Vol. 

 VII, No. 6. 



26. LOUGHRIDGE : American Journal of Science, Vol. VII (1874). 



27. HILGARD : Year-book U. S. Department of Agriculture, 1895. 



28. HOUSTON: Indiana Agricultural Experiment Station Bulletin 



No. 46. 



29. MULDER : From Mayer ; Lehrbuch der Agrikulturchemie, 2. 



30. WHEELER : Rhode Island Agricultural Experiment Station 



Reports, 1892, 1893, etc. 



31. Year-book U. S. Department Agriculture, 1895. 



32. LOUGHRIDGE : South Carolina Agricultural Experiment Station 



Second Annual Report. 



33. Association of Official Agricultural Chemists Report, 1893. 



34 Washington Agricultural Experiment Station Bulletin No. 13. 



35. Association of Official Agricultural Chemists Report, 1894. 



36. California Agricultural Experiment Station Report, 1890. 



37. SNYDER : Minnesota Agricultural Experiment Station Bulletin 



No. 29. 



38. SNYDER : Minnesota Agricultural Experiment Station Bulletin 



No. 47. 



39. LAWES AND GILBERT : Experiments on Vegetation, Vol. I. 



40. BOUSSINGAULT : Agronomic, Tome I. 



41. ATWATER : American Chemical Journal, Vol. VI, No. 8, and 



Vol. VIII, No. 5. 



42. HELLRIEGEL : Welche Stickstoffe Quellen stehen der Pflanze 



zu Gebote ? 



