1. ANGST E. C. 1923 The fouling of ship bottoms by bacteria. Report Bureau Construction and Repair United States Navy Department Washington.
2. BREED R. S. AND BREW J. D. 1916 Counting bacteria by means of the microscope. N. Y. Agric. Exp. Sta. Bull. 49.
3. COE W. R. 1932 Bull. Scripps Inst. Oceanog. tech. series 3 37-86.
4. Committee 1930 Manual of methods for pure culture study of bacteria. Soc. American Bact. Geneva N. Y.
5. CONN H. J. 1918 The microscopic study of bacteria and fungi in soil. N. Y. Agric. Exper. Sta. Tech. Bull. 34.