542 



Bulletin 107 



2. Ammonia production. — Ammonia was produced by all 



strains on nutrient broth, which is in accord with the statements 

 nf Thumm (31) (compare 20:754). The test was carried out 

 as follows: For the first of the series 125 cc. portions of nutri- 

 ent broth in Kjeldahl flasks were inoculated and incubated 10 

 days 111 the dark at room temperature (22 to 25 C). At the 

 end of this time determinations were made. Table 57 shows the 

 ammonia content of cultures and control in cc. of N/10 hydro- 

 chloric acid equivalent for the 125 cc. and it is also calculated to 

 a 100 cc. basis. 



TABLE 57. AMMONIA PRODI I lloN 



( Irganisin 

 number 



(XII. 

 ('XV. 

 CXXVII, 

 ('XX VI II. 

 CXXIX, 



exxx, 



CXXXIII, 



CXXXIV, 



CXXXV, 



CXXXVII, 



(XXXVIII, 



("XXX IX. 



('XL, 



CXLI. 



CXLII. 



Control, 



For the remainder of the series cultures were treated as 

 before except that i<><> cc. of media were used and the incuba- 

 tion period was 12 days at 20 C. The medium was identical 

 with that of the preceding series. 



