474 ISHIZUKA ; ON NITRATES STORED IN PLANTS. 



I paid also some attention to the products of transformation 

 of the nitrates. If all conditions are favourable, then of course 

 the nitrates are assimilated in the building up of proteids ; if, 

 however, all conditions for this process are not fulfilled other pro- 

 ducts might be formed and I suspected above all a gradual trans- 

 formation into asparagine in such cases. To compare the 

 amounts of nitrates and asparagine in the roots of RapJianus, 

 Brassica and Daucus three determinations were made : first just 

 after they had been harvested, then alter being kept for sixty 

 days in the dark in moist saw dust at the ordinary temperature, 

 and again forty days later. 



Objects. 



Dates of 

 examination. 



In dry matter. 



Percentages of 

 nitric anhydri'ie. 



Percentages of 

 asparagine. 



Raphauns sativus 



22 Nov. 

 24 Feb. 

 7 Apr. 



3- 2 5 

 2.85 

 2.56 



4- 35 



5- 66 

 6.18 



Damns Carota .*. 



22 Nov. 

 24 Feb. 

 7 Apr. 



0.048 

 0.046 



5-47 

 6.44 



7-41 



Brassica campestris 



22 Nov. 

 24 Feb. 



n6 

 0.90 



6.20 

 10.3S 



We here indeed observe a gradual decrease of nitrates 

 and increase of asparagine, but the latter increased so much 

 more that we must assume the larger portion of the asparagine 

 was produced either by decomposition of proteids or by the trans- 

 f or ination of other nitrogenous organic compounds. 



