154 



THE CHEMISTEY OF THE PLANT 



Formaldehyde — Con. 



Asparagin 



C4H8N2O3, (CO(NH2)- 

 -CH(NH2)-COOH). 



Chitin 



C18H30N2O12 



CHi 



Vanillin 

 CsHsOa 



Hadromal (composition uncer- 

 tain) 



hydrates. Found free in 

 minute quantities in leaves 

 when active photosynthesis is 

 occurring. 



This is found, especially in the 

 growing regions, in many 

 plants, e.g. asparagus, peas, 

 beans, vetches, beet roots, 

 potatoes, etc. 



This forms part of, or in some 

 cases is the chief constituent of, 

 the cell wall of many of the 

 lower plants, e.g. Myxo- 

 phyceae, Mucorales, Carpo- 

 myceteae. It was long con- 

 sidered a form of cellulose 

 ("fungus cellulose")- It 

 forms the body waU of insects, 

 crustaceans, etc. 

 Formed by the fermentation 

 of the seed pods ("beans") of 

 the Vanilla plant, whence it is 

 extracted by alcohol. It is 

 present in most if not all 

 lignified cell walls and is 

 possibly one of the substances 

 giving the cell wall the char- 

 acters that we call "lignifi ca- 

 tion" (see hadromal). 

 This is a substance separated 

 by Czapek from lignified cell 

 walls and believed by him to 

 be what gives them their 

 "lignified" character. On the 

 other hand many botanists do 

 not consider this as the impor- 

 tant body and ascribe lignifi ca- 

 tion to the presence in the cell 

 walls of coniferin and vanillin 

 (q.v.) and perhaps other sub- 

 stances. 



