114 LECTURE VI. 



In aqueous solution choline breaks down into glycol and trimethyl- 

 amine. It has also been found in a free state in plants. It is closely 

 related to another base, also found in plants, and especially in sugar- 

 beets, known as betaine, or oxyneurine. Its formula is : 



coo v 



It has been obtained from choline by oxidation. Other bases have been 

 isolated from various plants, which in part have been given characteristic 

 names; e.g., amanitine, from toad-stools; fagine, from buchu seeds, etc. 

 They are, however, all identical with choline. In toad-stools (Amanita 

 Muscaria) , there is found besides choline, another base called muscarine, 1 

 which is evidently an oxidation product of choline, and can also be obtained 

 from it by oxidation. It is commonly considered to be an aldehyde, 

 although its constitution has not yet been established positively: 



CHO 



CH 2 . N . (CH 3 ) 3 



AH 



Closely related to these is neurine, which has been isolated from the 

 brain by Liebreich. 2 Its composition is that of trimethylvinylammonium- 

 hydroxide : 



/CH 3 

 /CH 3 

 N^-CH 3 

 X CH = CH 2 

 X OH 



The second component of lecithin, the glycero-phosphoric acid, is easily 

 produced by uniting glycerol and phosphoric acid. 



The lecithins are widely distributed in the plant and animal kingdoms. 

 We could truly say that every cell contains lecithin. It occurs particu- 

 larly in animal tissues, in the brain, nerves, fish-eggs, yolk of eggs, and 

 in spermatozoa. It is also found in the muscles and the blood (in the 

 plasma as well as in the blood corpuscles) 3 in the lymph and leucocytes; 

 in fact, in every cell and in every organ. We find lecithin very widely 



1 O. Schmiedeberg and E. Harnack: Arch. exp. Path. Pharmak. 6, 101 (1877). 



2 Ann. 134, 29 (1865). 



3 Cf. E. Abderhalden: Z. physiol. Chem. 25, 65 (1898). 



