55o 
Odorous  Products  in  Plants. 
i  Am.  Jour.  Pharm. 
\  December,  1913. 
FORMATION  AND  DISTRIBUTION  OF  ODOROUS 
PRODUCTS'  IN  PLANTS.1 
By  Eugene  Charabot. 
The  study  of  the  mechanisms  which  regulate  the  formation  of 
the  odorous  matters  and  their  evolution,  the  investigation  of  the 
relations  existing  between  the  chemical  phenomena  which  modify 
these  substances  and  the  immediate  manifestations  of  the  life  of  the 
plant,  the  knowledge  of  the  part  played  by  the  essential  oils  in  the 
vital  economy,  constitute  so  many  enticing  problems  which,  it  will  be 
readily  conceived,  have  a  capital  importance,  not  only  from  the 
point  of  view  of  rational  cultivation  and  of  judicious  harvesting, 
but  also  from  the  point  of  view  of  the  rational  extraction  of  the 
perfume  of  the  plant. 
To  this  study  I  have  devoted,  either  alone  or  in  collaboration, 
principally  with  M.  Al.  Hebert,  more  than  ten  years  of  research 
work. 
The  question  embraces :  the  formation  and  circulation  of  the 
odorous  compounds ;  their  evolution  and  the  mechanism  of  this 
evolution ;  the  genesis  of  the  odorous  matters  and  the  physiological 
role  of  the  perfumes. 
Formation  and  Circulation  of  the  Odorous  Compounds. — The 
odoriferous  plants  form  two  very  distinct  groups  as  regards  the 
distribution  of  their  aromatic  principles  among  the  various  organs. 
In  some  the  essential  oil  makes  its  appearance  in  the  green  organs ; 
in  the  others  it  exists  exclusively  in  the  flowers.  Thus  it  will  be 
necessary  to  consider  separately  the  perfume  in  the  entire  plant  and 
the  perfume  in  the  isolated  flower. 
The  Perfume  in  the  Entire  Plant. — We  have  experimented  with 
various  representatives  of  the  vegetable  kingdom,  belonging  to  differ- 
ent families  and  containing  the  most  diversified  chemical  substances, 
and  we  have  arrived  at  the  following  conclusions  : 
The  odorous  kinds  of  matter  make  their  appearance  in  the  young 
green  organs.  They  continue  to  form  and  accumulate  until  the 
flowering  period,  but  with  an  activity  which  slackens  more  or  less 
appreciably.   They  migrate  from  the  leaf  into  the  stem,  and  thence 
1  Lecture  delivered  at  the  Pharmaceutical  meeting  of  the  Philadelphia 
College  of  Pharmacy,  October  17,  1913. 
