ASPARAGINE NUTRITION OF PLANTS. 



199 



The determination of asparagine in the control shoot No. 1, 

 was made after the removal of the cotyledons (April 1), when 

 the experiment proper commenced. If we compare this result 

 with that yielded by the control shoot No. 2, we find an increase 

 of asparagine in percentage of dry matter, due probably to the 

 gradual conversion of other amido-compounds into asparagine. (I) 

 The fact that in the control case No. 3, where the cotyledons 

 had not been removed, a smaller percentage of asparagine was 

 found than in No. 2, may probably be due to the galactans and 

 other carbohydrates gradually becoming soluble and getting 

 consumed in support of respiration, thus protecting proteids as 

 well as amido-compounds from further changes, and retarding 

 the production of asparagine. 



The principal conclusions which we can draw from the 

 results obtained are : 



(1) . Glycerol and methyl alcohol supplied by the roots, can 

 not only hinder the production of asparagine in the shoots, but 

 are also capable of diminishing the amount already formed. 



(2) . Glycerol is much more effective than methyl alcohol. 

 It also forms sugar in the cells. (2) 



(3) . Since shoots have been found to grow better in solu- 

 tions of methyl alcohol and glycerol than in water, and also to 

 show the presence of dissolved proteids by the nitric acid test, 

 it is safe to assume an increasing protein production in the shoots 

 thus nourished; in other words methyl alcohol, as well as gly- 

 cerol, can serve for the regeneration of proteids from asparagine, 

 and as this process can go on in perfect darkness, light must be 

 denied to have any direct action in supporting it. (3) 



(1) Compare O. Locw. This Bulletin, Vol. II. No. 2. 



(2) This formation of sugar is in accordance with the observations of Laurent, 

 Ar. Meyer, and Th. Bokomy. The latter author has also observed starch formation 

 from methyl alcohol under the influence of daylight. 



(3) It is however indirectly of great importance, because it yields the necessary 

 carbohydrates ; for the more sugar there is present in a cell, the quicker will 

 asparagine be transformed into proteids. 



