﻿228 16 



volume consisted of H^SO^. By this process were precipitated peptons and basic 

 nitrogeneous substances i. e. nuclein-bases and Lysin, Histidin and Arginin besides 

 Ammonia. [Hausmann 1899, p. 95 & 1900, p. 136] and perhaps Phenylalanin [Schulze 

 & Winterstein p. 210]. An estimation of the amount of nitrogen in the filtrate 

 stated the amount of monamino-acids; the difference between tliis amount and the 

 amount found in the filtrate of the tannic acid precipitation stated the amount of 

 peptones and basic compounds. In the bibliography it has been stated that excess 

 of tannic acid as well as of phosphotungstic-acid does not dissolve the precipitate, 

 a phenomenon I have also ascertained by experiments. It must be noted in this 

 connection that the experiments have always been carried out uniformly with 

 regard to crushing, precipitating e. t. c. within the same experimental series. 



In the analyses of the seedlings used for the experiments on translocation of 

 materials the method I used was somewhat different from the above mentioned 

 procedure. The alcoholic extract was filtered from the undissolved parts, which 

 were washed ') with alcohol (of the same strength). The filtrate together with the 

 washing alcohol was evaporated nearly to dryness, the residue was dissolved in 

 hot water and transferred to a measuring flask of 50 c. c. capacity. When the 

 liquid had cooled, the flask was filled with water to the mark and shaken. Of 

 this liquid two portions of 10 c. c. were analysed to ascertain the amount of nitro- 

 gen. The residue was precipitated by tannic acid and a few drops of lead acetate; 

 the measuring flask was again filled with water to the mark and was put aside 

 till the next day, when the liquid was filtered and estimation of the amount of 

 nitrogen was made of the filtrate. Besides estimations of the amount of nitrogen 

 of the undissolved parts of the objects were made, these being dried, triturated and 

 weighed. Of the results the whole amounts of nitrogen of the proteids and of the 

 amides were calculated. 



For estimation of nitrogen by Kjeldahl's process I used ^ sulphuric acid in 



n 

 the receiver and ^å sodic thiosulphate for the titration. The hyposulphite was 



standardized by KJO^ . 



Analyses of sugars were carried out in the following way: Equal amounts of 

 the alcoholic extract of the plants were evaporated to dryness on water-bath and 

 the residues dissolved in hot water. The portions were each transferred to a measu- 

 ring flask and water was added to the mark. Of the filtrated liquids were used 

 1) equal quantities of each portion for analyses on "reducing" sugar by Meissl-Allihn's 

 weighing-methods and 2) equal quantities for estimation of "non-reducing" sugars 

 these being inverted by being boiled with diluted sulphuric acid on water-bath for 

 l'/ä hours; then they were neutralized by NaOH and the sugar-estimations were 

 performed in the above mentioned manner. The amounts of sugars were stated 

 as glucose. 



') The washing wa.s not ended until 20 c. c. of the wasliing.s contained 01 mgr. N. at most. 



