A CONTRIBUTION TO THE KNOWLEDGE OF ARGININ. 1 3 



may be due to experimental error ; so there is no doubt that the 

 crystals obtained were those of arginin. The quantity of the 

 arginin crystals obtained amounted to about $% of the proteids 

 used, (calculated as pure proteids), that is to say, nearly 10% 

 of the nitrogen in the proteids was contained in the arginin. As 

 I found that about 1 $% of the nitrogen in the proteids are 

 contained in the phospho-tungstic precipitate (organic bases) 

 formed by the action of hydrochloric acid, we may conclude that 

 nearly § of the organic bases formed, consist of arginin. 



The mother liquor of basic arginin silver nitrate crystals 

 was diluted with water, and silver was precipitated with hydrogen 

 sulphide. The filtrate from the silver sulphide was evaporated 

 and concentrated, and precipitated with phospho-tungstic acid. 

 The precipitate was washed with 5% sulphuric acid, strongly 

 pressed between the filters and then decomposed with caustic 

 baryta. The dissolved baryta was removed by carbonic acid, 

 evaporated, once more filtered, and a mercuric chloride solution 

 was added, whereby a white precipitate was obtained, perhaps 

 due to histidin (?) but too little to confirm. The filtrate from 

 the mercuric chloride precipitate was diluted with water and 

 the dissolved mercury was removed by hydrogen sulphide, 

 filtered, and the filtrate was evaporated and concentrated. No 

 crystals were obtained after long standing. Therefore lysin 

 was probably not present. 



b). Etiolated shoots of Cryptomeria japonica. 



Etiolated shoots 6-8cm. high, grown in the purified sea sand, 

 were dried and powdered. 40 grams of this dry powder were 

 extracted with about one litre of water at 50-6o°C. After two 

 hours, the extract was cooled and filtered. To the filtrate, an 

 excess of basic lead acetate was added until no more precipitate 

 was formed, and filtered. The excess of lead in the filtrate was 

 removed by sulphuric acid. The filtrate from the lead sulphate, 

 was precipitated by phospho-tungstic acid, whereby a white 

 precipitate was formed in considerable quantities. The precipi- 

 tate was treated in the same way as described before, and 

 crystals of basic arginin silver nitrate were obtained in a to- 

 lerably large quantity. But in this case it was too difficult to 

 get the crystals pure, owing to the excessive reduction of silver. 

 Therefore it was impossible to decide how much arginin was 



