14 PHYSIOLOGY OF THE IXVERTEBRATA. 



ralladiu {BrriclUc dcr Dciitschcn Botan. f/csdlscha/f, vol. 6, 

 p. 296), and Drs. Schiilze and Kisser (Laiidw. Vcrsnchs-titat., 

 vol. ^6, p. 1), have shown that vegetal protoplasm can be 

 made to yield ty rosin, leucin, xanthine, hypoxanthine, and 

 similar compounds, which are undoubtedly some of the pro- 

 ducts of the decomposition of albumin occui'ring in the bodies 

 of living animals. If protoplasm or albumin gives rise to 

 such compounds as the above, we have good reason to believe 

 that its constitution is more complex than Loew and Bokorny 

 would have us suppose. Many of the substances formed 

 during the decomposition of albumin have been artificially 

 prepared in the laboratory. For instance, leucin is very 

 largely diffused in the animal oi'ganism, and has been obtained 

 artificially by oxidising amylic alcohol with potassium bi- 

 chromate and sulphuric acid, and then distilling, when the 

 following reaction occurs : 



2C,H„H0 + 0, = 20,H^COH + 2Hp. 



[Amylic alcohol.] [Valeric aldehyde.] 



When valeric aldehyde is treated with ammonia, valeral 

 ammonia is formed, and if the latter compound is digested 

 with hydrocyanic and hydrochloric acids it is converted into 

 leucin : 



(n) C,H,^.COH + NH3 = C,H^CH(NH,)OH. 



[Valeral ammonia.] 



(h) C,H„CN(NH,,)OH + HCN + KP = 



C,H„Cn|^^(3^ 4- NH, 



[Lencin.] 



Amido-isovaleric acid (a substance which occurs in the 

 pancreas of the ox), amido-butyric acid, and amido-propionic 

 acid, have been obtained by Schiitzenberger* from albumin ; 

 and all these substances have been obtained artificially in the 

 laboratory. 



* See Comptes-RemJus, vols. 81 and 84. 



