1IIPPURIC ACID IN SOILS. 223 



Several bottles were examined for undecomposed hippuric 

 acid, but none could be found. 



The bacterial vegetation consisted mainly of micrococci. 



Results. 



Hippuric acid and its sodium salt are not absorbed by the 

 soils tested. 



Decomposition of hippurates proceeds more quickly in the 

 surface soil than in the subsoil ; this decomposition is attended 

 with liberation of ammonia, and is chiefly dependent upon the 

 action of micrococci. 



Note to the Preceding. 



BY 



Prof. Oscar Loew. 



The fact observed by Yoshimura that nitrification does not 

 take place in solutions of sodium hippurate is in accordance 

 with other similar observations. The nitrifying microbes, able 

 to assimilate ammonium carbonate, according to Hiippe and 

 Winogradszki, cannot assimilate ammonium formate, and do 

 not develope well upon ammonium oxalate,* 0 as I have myself 

 ascertained. In my experiments, the sterilised solutions con- 

 tained, (besides 0.5 per mille of one of these salts), 0.5 per 

 mille each of neutral potassium phosphate, and magnesium 

 sulphate, and were infected from a culture obtained from garden 

 soil exhibiting a moderate nitrifying activity. The flasks, holding 



(1) The objection that the want of nitrification is not under all conditions a 

 reliable sign of the absence of nitromonas, seems to me not tenable. In those cases, 

 however, in which other microbes are also present, the ammonium nitrite formed can 

 easily be destroyed. 



