SUPPLEMENT 



49 



1. 27, for consumption read storage 



I. 31, after leaves, read The same thing takes place in cultures carried out 

 under conditions of drought ; the older parts dry up, since they surrender 

 water to younger parts (PRINGSHEIM, 1906). In these cases the plant uses up 

 some of the materials which one is accustomed to regard not as reserves but 

 as constructive substances. 



11- 37, 50, for amides read amino-acids 



II. 48-9, for bodies whose constitution is very different from its own read 

 amino-acids. 



I. 56, for amide bodies read amino-acids 



174, 1. i, for amides read amino-acids 



II. 4-20, for In the first place ... by analysis, read Let us consider first 

 the general nature of the mixture of amino-acids in different plants. The 

 following table taken from ABDERHALDEN (Phys. Chem.) gives us such in- 

 formation ; it shows us how many grams of each substance may be obtained 

 from 100 g. of proteid : 



Glycocoll . 



Alanin 



Amino-valerianic 



Leucin 



Prolin 



Phenylalanin 



Glutaminic acid 



Aspartic acid 



Tyrosin 



Cystin 



Histidin 



Arginin 



Lysin 



Tryptophane 



acid 



Lupinus albus 



(Conglutin) 



0-8 



2-5 

 I.I 



6-75 

 2-6 



3-r 

 6-5 

 3-o 



2-1 



(present) 

 0-65 

 6-6 



2-1 



(present) 



Picea excelsa 



06 

 1-8 



(present) 

 6-2 

 2-8 



1-2 



7-8 

 1-8 



1-7 



0-25 (?) 

 0-62 

 10-9 

 0-25 

 (present) 



Cannabis 

 (Edestin) 



3-8 



3-6 



(present) 

 20-9 



i-7 

 2-4 



6-3 

 4-5 



2-1 



O-25 



I-I 



11.7 



i-o 

 (present) 



It would thus appear that the same amino-acids are everywhere present, 

 but in varying quantities, and this conclusion remains practically unaltered 

 when we take into account other proteids also. The same amino-acids (phenyl- 

 alanin excepted) are obtained also in tryptic digestion ; this much we do 

 know, but there are no quantitative statements available. Those at least 

 dealing with the analysis of the acids have more the character of rough esti- 

 mates. These amino-acids (with the exception of glycocoll and alanin) also 

 occur in etiolated plants, but in quite different proportions, and instead of 

 glutaminic and aspartic acids, we find the amides, glutamin and asparagin. 

 These amides often accumulate very markedly ; thus glutamin, found in 

 Cucurbita, Ricinus, and Cruciferae, may form 2\ per cent, of the dry weight, 

 while in Papilionaceae, Gramineae, and other plants the asparagin found 

 there may amount to 20 per cent, of the dry weight. There can be no doubt 

 (SCHULZE, 1906 ; PRIANISCHNIKOW, 1904) that in the formation of asparagin 

 we have to do with a secondary alteration in the substances produced by 

 proteid hydrolysis, but it is out of the question that all the asparagin arises 

 by an amide transformation of aspartic acid. Indeed it may be shown that in 

 proportion as asparagin appears other amino-acids disappear ; the formation 

 of asparagin runs parallel, not with the progressive hydrolysis of proteid, but 

 with the disappearance of these acids. 



1. 30 P. 175, 1. 12, for Finally, it would appear ... in the plant, read 

 How asparagin and glutamin are formed from the amino-acids which dis- 

 appear, e.g. leucin, tyrosin, &c., is unknown. SCHULZE assumes that these 

 substances are either further split up hydrolytically, or that they are oxidized ; 

 JOST D 



