PHOSPHOROUS SUBSTANCES OF THE CELL. 137 



them into alcohol the filtrate in the case of the thyminate 

 is found to contain the nuclein base, whereas in the case of 

 the nucleic acid no base is split off. 



Turning next to another group of bodies, it has been 

 found that some of the nucleic acids yield carbohydrates 

 among their decomposition products. Thus, working on 

 the nucleic acid of yeast, Kossel l obtained evidence of 

 a carbohydrate in that molecule, and in a later paper 2 de- 

 scribes the preparation of an osazone melting between 204 

 and 205° C. and of a second melting at 105° C. The first 

 he shows to be due to a glucose which does not ferment with 

 yeast, but which reduces Fehling's solution. The second 

 osazone is probably due to a pentose as shown by the produc- 

 tion of furfurol from it. It is to be noted that the carbo- 

 hydrate molecule belongs to the nucleic acid part of the 

 nuclein not to the proteid portion. He was not able to obtain 

 any carbohydrate from the nucleic acid prepared from salmon 

 spermatozoa. Hammarsten a describes the preparation of 

 a substance from ox-pancreas, very closely related to the 

 nucleins, from which he was able to obtain a body reducing 

 Fehling's solution by boiling the preparation with weak 

 sulphuric acid. From the decomposition products he pre- 

 pared an osazone melting at 158 to 160° C, easily soluble 

 in alcohol or ether and which could be crystallised from its 

 alcoholic solution by adding warm water and then allowing 

 it to cool. The sugar did not ferment with yeast and its 

 osazone did not correspond with that of any known sugar. 

 It is probably a pentose. Another nucleic acid which has 

 given evidence of the presence of a carbohydrate is that 

 prepared from the thymus. On heating this for two hours 

 in a Papin's digester at 150° C. with 20 per cent, sul- 

 phuric acid, Kossel and Neuman 4 found levulinic acid 

 among the bodies into which it had been decomposed ; and 



1 Kossel : Arch. f. (Anat. u.) Physiol., 1891, S. 181. 

 -Kossel: Ibid., 1893, S. 157. 



3 Hammarsten : Zeitschr. Physiol. C/iem., Bd. 19, S. 19, 1894. 



4 Kossel u. Neumann: Per. d. d. chem. Gesell., Bd. 27, S. 2215, 

 1894; and Kossel: Arch.f. (Anal, u.) Physiol., 1894, S. 536. 



