40 KozLowsKi : Primary Synthesis of Proteids 



of the synthesis of inorganic substances, until we have proved that 

 they arc not produced from decomposition of proteids. In the 

 meantime Hornbcrger and Raumer "^ applied the method of deter- 

 mination of proteids newly introduced by Stuzer. This method en- 

 ables us to determine the amount of these bodies from other 

 nitrogen compounds in plants. From the distribution of proteids 

 and other nitrogen compounds in Indian corn, Ilornberger and 

 Raumer deduced that the amides in plants are not only derivatives 



■ 



of proteids, but also their predecessors produced synthetically. 



This result was confirmed by Hornberger^f who experimented 



upon Si?iapis alba and by i^mmerling who had then completed his 



long series of experiments. | 



On the other hand a recent publication gives a support for the 

 ' second part of the supposition concerning the amides as a link be- 

 tween inorganic bodies and proteids. Barthold Hansteen culti- 

 vated Lcvina in solutions of asparagih and glucose in dark- 

 ness and found an obvious increase of proteids. The same result 

 was obtained with carbamide and cane sugar as well as with salts 

 of ammonia (ammonium chloride and sulphate) w^hile leucin, 

 cretin and alanin showed themselves unable to serve as proteid- 

 producing materials. § The last observation concerning salts 

 of ammonium if proved to be true cannot be generalized, for ex- 

 periments made under the most stringent conditions have proved 

 that phanerogamic plants cannot use ammoniacal salts as a source 

 of nitrogen, although that capacity is possessed by fungi, 



So regarding the metamorphsis of nitrogen in plants we know 

 that by the oxidation of the nitrates of the soil it is transformed 

 into reduced nitrogen of amides, which by combination with 

 carbohydrates produce proteids. 

 ' We, therefore, have to answer two questions : 



1. In w^hat organs of the plant does this transformation or its 

 particular phases take place ? 



2. What compounds are hitermediate between nitric acid and 



*Landw. Jahrbiicher, ii : (1882). 

 ■j-Landw. Versuchsstationeii, 32 : 415. 1885. 

 J T.andw. Versuchsstationen, 34 : (1887). 



\ Beitrage surKenntniss der Eiweissbildung in phanerogamen Pflanzen. Bcrichte 

 deutsch, hot. Ges. 14: 362. 1896. 



