188 Direct Assimilation of Ammomiim Salts hy Plants 



The plants in Nos. 7 — 10 grew quite vigorously and possessed a 

 dark green colour ; Nos. 1 — 3 were also good, while 4 — 6 were stunted, 

 No. 6 especially being very poor and ceasing to grow after 12 — 14 days. 

 This is shown in the table by the slight amount of dry matter formed 

 and of nitrogen assimilated. 



The average amount of nitrogen in each seed was 071 mgm. 



Table I. Wheat in Sand Cultures. 



At the close of the experiment portions of the sand in each bottle 

 were carried over to flasks containing Omelianski's solution and showed 

 the absence of nitrifying organisms in bottles 1 — 6. 



Series II. Wheat grown in Water Culture. This series was carried 

 out in order to corroborate the results of the previous experiments. 

 The treatment of the seed and seedlings was in every respect similar 

 to that of the foregoing series, and the seedlings were transplanted 

 when about 7 cm. high. Woulff's bottles of 8.50 c.cm. capacity were 

 fitted with aeration tubes and Pasteur- Hansen flasks and were filled 

 with the following solution : — 



- + 1000 c.c. distilled water 



To Nos. 3 and 4, 5 and 6, 2 grams CaCOj was added. After the 

 bottles had been sterilised in the autoclaves, 10 c.c. of a sterile solu- 



