— 184 — 



Both mixtures were left to incubate at 37° for 96 hours. 

 On the filtrates A and C, obtained as before, the following dete 

 minations were made : 



1. 40 e. e. of filtrate A gave 0.1356 grms. of dry residue, i. e. 

 3.39 o/oo; 



40 e. e. of filtrate C gave 0.1000 grms. of dry residue, i. e. 

 2.5 o/oo. 



The residues incinerated left : 



0.0452 grms. of ash, i. e. 1.13 «/oo in filtrate A; 



0.0416 grms. of ash i. e. 1.04 o/oo in filtrate C; 



and consequently : 



0.0904 grms. of organic matters, i. e. 2.26 «/oo in filtrate A ; 



0.0584 grms. of organic matters, i. e. 1.46 °/oo in filtrate C. 



2. Nitrogen estimation. In 20 e. e. of each filtrate the ni- 

 trogen was estimated. To neutralise the ammonia resulting were re- 

 quired : 



3.5 e. e. of " /io HCl, which correspond to 0.0245 «/o nitrogen in 

 filtrate A; 



2.25 e. e. of "/io HCl, which correspond to 0.0157 "/o nitrogen in 

 filtrate C. 



Results an increase of 0.0088 grms. nitrogen in 100 e. e. of filtrate 

 A, corresponding to 10 grms. of brain. 



3. Furine nitrogen estimation. The Silver compound yiel- 

 ded in 100 e. e. of filtrate A, by the ammoniacal silver nitrate, requi- 

 red, according to Kjeldahl, 1.65 e. e. of "/io HCl, which correspond 

 to 0.00231 o/o purine nitrogen. 



No purine bases were precipitated in the filtrate of the control- 

 research. 



4. Phosphorus estimation. In 40 e. e. of each filtrate the 

 phosphorus was estimated. To dissolve the molybdenum phosphate pre- 

 cipitated were required : 



17.7 e. e. of "/., NaOH , corresponding to 0.00978 o/o phosphorus 

 in filtrate A ; 



10.8 e. e. of " i NaOH, corresponding to 0.00597 o/o phosphorus in 

 filtrate C. 



Results an increase of 0.00381 grms. phosphorus in 100 e. e. of 

 filtrate A. 



E X p e r i m e n t No. 7. 



On a brain weighing 52 grms. and prepared as in previous expe- 

 riments the following researches were made : 



