26 ESSENTIALS OF CHEMICAL PHYSIOLOGY 



yields on decomposition not only glycerin and a fatty acid, 

 but phosphoric acid, and an alkaloid [N.(CH 3 ) 3 C 2 H 6 2 ] called 

 choline in addition. Lecithin is found to a great extent in the 

 nervous system, 1 and to a small extent in bile. Together with 

 cholesterin, a crystallisable, monatomic alcohol (C 27 H 45 .HO) which 

 we shall consider more at length in connection with the bile, it is 

 found in small quantities in the protoplasm of all cells. 



1 See further under Nervous Tissues, Lesson XXII. 



