228 SCIENCE PROGRESS. 



they do not occur, for they may be present in such small 

 quantities as to defy isolation, or the plant may consume 

 them as soon as they are formed. Also, some of the 

 artificial compounds may not be primary products, but due 

 to secondary reactions. Moreover, the products that result 

 from the oxidation of proteins in vitro are not those found 

 in seedlings, although closely connected in some cases, as 

 might be expected. If, too, the process were one of oxida- 

 tion, it is difficult to see why the increase of sulphates in 

 the early periods of germination of Litpinus luteus should 

 not correspond with the amount theoretically obtainable 

 from the decomposed proteins, this approximation being- 

 only acquired in the later stages. These facts are quite 

 explicable, if the process is one of hydrolysis. Further, 

 Pfeffer, has stated, that if the reserve-proteins are com- 

 pletely converted into asparagin, a residue of carbon and 

 hydrogen must remain, since asparagin has a percentage- 

 composition that is richer in nitrogen and poorer in carbon 

 and hydrogen than proteins. Now Palladin and Low re- 

 gard the matter in this light, and assume that these 

 residues are oxidised to form carbohydrates, which Palladin 

 regards generally as products of proteinic oxidation. But 

 Prianischnikow, relying on the results obtained by Schulze 

 and himself with Vicia sativa, shows that, through subtract- 

 ing from Lieberkuhn's formula for protein, of which Palladin 

 makes use, an approximate computation of the total amount 

 of substance formed from reserve-proteins in this case, 

 there is left a small residue of carbon, that need be only 

 hydrolysed to form carbohydrates. Thus the objection of 

 Low and of Palladin falls to the ground. 



But the view of hydrolysis is still further strengthened 

 through observation of the occurrence of proteases in ger- 

 minating seeds, which exercise in vitro a hydrolytic action 

 qualitatively similar to that of pepsin. 



When these considerations are justly weighed, but one 

 conclusion can be made, namely, that of Schulze and 

 Prianischnikow, that the process through which reserve- 

 proteins are converted into amido-compounds is hydrolysis, 

 not oxidation. 



