402 THE GLANDULAR ORGANS. 



>epa rated from the cellular elements and remain behind. The cells 

 are thoroughly extracted with water and with dilute saline solution, 

 by decantation, until all soluble substances have been removed. 

 They are then digested with gastric juice. The non-digested residue 

 is extracted with acidulated alcohol and subsequently with ether, to 

 remove pigments, cholesterin, and fats. It is then treated with 

 weak ammonia-water, which dissolves the iron-containing nucleins. 

 From this solution they are precipitated with absolute alcohol when 

 added in excess. The resulting material constitutes the hepatin of 

 Zaleski. The other iron-containing nuclein is apparently present 

 in the liver as a nucleo-albumin, and is found in this form in the 

 saline extract of the cells. To demonstrate its presence, the previ- 

 ous extraction with saline solution is omitted. If the residue of 

 nucleins, which remains after digestion with gastric juice, is then 

 placed in a solution of ammonium sulphide, a greenish color gradu- 

 ally develops which ultimately turns black, owing to the forma- 

 tion of sulphide of iron. The hepatin itself does not give this 

 reaction. Neither substance gives up its iron, even when treated 

 with acidulated alcohol l for days, thus differing from the iron albu- 

 minate, which behaves in this manner exactly like inorganic prep- 

 arations of iron. 



Isolation of the Iron-containing Albuminates. In this case it is 

 not necessary previously to wash out the blood. The organ is 

 minced without further preparation, and is placed in from three to 

 four times its volume of water. The mixture is slowly heated, 

 boiled for about fifteen minutes, and filtered on cooling. The filtrate 

 is carefully precipitated with a 10 per cent, solution of tartaric acid. 

 The resulting flocculent material, which presents a brown color, is 

 collected on a filter, washed with a weak solution of tartaric acid, 

 then with 50 per cent, alcohol, and finally with absolute alcohol. It 

 contains about 6 per cent, of iron. It is soluble in solutions of the 

 alkalies, and does not react with ammonium sulphide at once. After 

 a few minutes, however, the solution becomes darker and gradually 

 turns black. On treating with acid alcohol (see above) the iron is 

 split off, and can be directly demonstrated by testing with potassium 

 ferrocyanide or potassium sulphocyanide. Sehmiedeberg has termed 

 the substance in question ferrctthi, and regards it as a ferri-albuminic 

 acid. 



Ferments. The ferments which occur in the liver are as yet but 

 little known. It appears that several varieties exist, and it is quite 

 probable that they are intimately concerned in the various functions 

 of the organ. Some of the ferments are rm/f/r/wx, and one of these 

 in turn is an atfleJn/daxc, viz., a ferment that is capable of oxidizing 

 salicylic aldehyde to the corresponding acid. The existence of 

 another ferment which is capable of transforming firmly combined 

 nitrogen into amido-nitrogen seems to "have been established by 



1 The acidulated alcohol contains 10 volumes of ;i *2~) per cent, solution of hydro- 

 .chloric acid and 1)0 volumes of 96 per cent, alcohol ( Bung^S fluid). 



