FIXATION OF NITROGEN BY FUNGI 



181 



field of controversy and the methods of this investigator were 

 kept especially in mind. 



As is well known, but seldom mentioned by investigators, 

 the carbohydrates used in the culture media cause serious diffi- 

 culties in the Kjeldahl method and even more serious ones in the 

 Folin method. These seemed at first to be insurmountable, for 





Ex. — CxHAUST. 

 S.P — Suction PuMF. 

 T.T — Test Ti/bc. 



Fig. 1. After the sample has been digested in the test-tube, t.t., in the upper 

 figure, it takes the position B, in the detail figure below, where it is connected 

 with the wash-bottle, A, and the receiving flask, C. A current of air from a 

 compressor is admitted at the point indicated by the arrow and the ammonia is 

 driven over from A into the receiver, C, where it is caught in a weak solution of 

 hydrochloric acid and Nesslerized. The wash bottle A contains strong sul- 

 phuric acid to arrest any ammonia or other combined nitrogen that might be 

 contained in the air current. 



