BY JAMES M. PETRIE. 819 



The purin bases were first observed in plants by Schiitzenberger, 

 who found them in yeast. Kossel(55) noticed that, by long- 

 continued boiling with water, the nucleins of yeast break up and 

 purins, chiefly hypoxanthin, are obtained; the latter was isolated 

 from black mustard-seeds, wheat, lupin-seeds, and spores of 

 Lycopodium. Chittenden, (56) too, has shown that, by boiling 

 fibrin with water for twenty-four hours, small quantities of 

 hypoxanthin were obtained; and, further, that protein, when 

 warmed for several days in contact with gastric or pancreatic 

 juice, yielded hypoxanthin. Now when seeds are extracted with 

 cold water, the ferments accompany the proteins into the extract; 

 and so we have all the conditions for incipient hydrolysis and 

 formation of traces of purin. This fact has to be remembered in 

 examining such substances for small quantities of these bodies. 



Xanthin and the methyl-xanthins have been known, for well 

 nigh a century, to be present in tea and coffee seeds, in cacao 

 seeds, and in cola-nuts. 



Hypoxanthin is present in most leguminous seeds, in seeds of 

 cereals and a number of other plants. 



Guanin has a very wide distribution; it was obtained by 

 Schulze(57) from a large number of leguminous seeds. 



Allantoin, which is a decomposition-product of trioxypurin, 

 was discovered in the bran of wheat by Richardson and Cramp- 

 ton, (58) and confirmed by Schulze(59); the amount present was 

 about 0*5%. 



5. Lecithins. — The phosphorus-containing constituents of 

 plants which are dissolved out by absolute alcohol and ether, are 

 grouped together under the new name of the phosphatides^*)^ 

 They include true lecithins, and also certain compounds of lecithin- 

 like bodies with carbohydrates, etc. The most recent work on the 

 plant-phosphatides is that of Winterstein,(61) who discovered that 

 these complex bodies yield, on hydrolysis, hexoses and pentoses 

 in very varying amounts; as, for example, those isolated by ether 

 from Triticum vulgare contain 16 % of carbohydrate (galactose and 

 d. glucose), from Lupinus albus 13 %, from L. luteus 1 %, and 

 from Vic'ia aativa 3%. It is not yet known whether these are 



