LITERATURE CITED. 



1) Cook, F. C, Hutchison, R. H., and Scales, F. M. 



1914. Experiments in the destruction of fly larvae in horse .manure. U. S. 



Dept. Agr. Bui. 118, 26 p., 4 pi. 



2) . 



1915. Further experiments in the destruction of fly larvae in horse manure. 



Dept. Agr. Bui. 245, 22 p., 1 pi., 1 fig. 



3) Cook, F. C. 



1916. Boron: Its absorption and distribution in plants and its effect on growth. 



In Jour. Agr. Res., v. 5, no. 19, p. 877-890. 



4) FoLiN, Otto, and Macallum, A. B. 



1912. On the determination of ammonia in urine. In Jour. Biol. Chem., 



V. 11, no. 5, p. 523-525. 



5) KlONKA. 



1909. Die Gif tigkeit von ' ' Kalkstickstoff ' ' und ' ' Stickstoffkalk. ' ' In Fuhlings 

 Landw. Ztg., Jahgr. 58, Heft 11, p. 397-404. 



6) Pranke, E. J. 



1913. Cyanamid. Manufacture, Chemistry, and Uses. 112 p. Easton, Pa. 



7) Wiley, H. W., Editor. 



1908. Official and provisional methods of analysis. Association of Official 

 Agricultural Chemists. U. S. Dept. Agr. Bur. Chem. Bui. 107, 

 (rev.), 272 p., 25 fig. 



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