388 NATHAN BERMAN AND LEO F. RETTGER 



Rettger, L. F., Berman, N., and Sturges, W. S. 1916 Further studies on bac- 

 terial nutrition. The utilization of proteid and non-proteid nitrogen. 

 J. Bact., 1, 15-33. 



Rice, F. E. 1915 Studies on the action of erepsin. J. Am. Chem. Soc, 37, 

 1319-33. 



RiVAS, D. 1912 Studies on indol. Centralbl. Bakt., Abt. 1, Orig., 63, 547-50. 



RosENOW, E. C. 1912 On the toxicity of broth, of pneumococcus broth cul- 

 ture filtrates, and on the nature of the proteolytic enzyme obtain- 

 able from pneumococci. J. Inf. Dis., 11, 286-93. 



Sears, H. J. 1916 Studies in the nitrogen metabolism of bacteria. J. Inf. 

 Dis., 19, 105-37. 



Smith, Th. 1897 A modification of the method for determining the production 

 of indol by bacteria. J. Exp. Med., 2, 543-7. 



SoEENSEN, S. p. L. 1908 Enzymstudien. Biochem. Z., 7, 45-101. 



Sperky, J. A. and Rettger, L. F. 1915 The behavior of bacteria towards 

 purified animal and vegetable proteins. J. Biol. Chem., 20, 445-59. 



Taylor, A. E. 1902 Ueber Eiweisspaltung durch Bakterien. Z. physiol. Chem., 

 36, 487-92. 



Vernon, H. M. 1904 The peptone-splitting ferments of the pancreas and 

 intestine. J. Physiol., 30, 330-69. 



