AS RESERFE-MATERIAL IN PLANTS. 



33 



some reactions, of which the living protoplasm is not capable on 

 account of changing too quickly. — As to the great difference 

 between the active and the passive albumen, convincing evidence 

 has been furnished, and we recall here the more striking points 

 of this chemical difference : 



1. The power of combining with water is greater with the 

 active than with the passive albumen ; 



2. Coffein and antipyrin exert action upon the active, not 

 upon the passive albumen ; 



3. Alcohol of 10-20 per cent, vapors of ether, very dilute 

 acetic acid, change the active, but not the passive albumen ; 



4. Active albumen absorbs ammonia and turns thereby in- 

 soluble, while passive albumen remains indifferent. 



5. Active albumen reduces highly diluted alkaline silver 

 solutions, passive albumen does not. 



