552 
Odorcms  Products  in  Plants. 
J  A.m.  Jour.  Pharm. 
\   December,  1913. 
adapt  them  for  a  more  intense  chlorophyllian  function  are  favorable 
at  the  same  time  to  esterification,  because  this  function  is  favorable 
to  the  mechanical  elimination  of  water. 
Thus  the  chlorophyllian  function  tends  to  acquire  a  new  signifi- 
cance :  it  not  only  assures  the  fixation  by  the  plant  tissues  of  carbonic 
acid  gas,  it  not  only  effects,  by  favoring  transpiration,  the  circulation 
of  the  liquids  which  carry  and  distribute  the  principles  necessary  to 
the  mineral  nutrition  of  the  plant,  but  it  also  activines,  once  the 
carbon  is  assimilated,  the  condensations  which  enable  the  passage 
from  a  simple  chemical  structure  to  one  of  the  innumerable  complex 
structures,  the  study  of  which  taxes  all  the  ingenuity  of  the  chemists. 
When  the  alcohol  is  capable  of  readily  parting  with  the  elements 
of  water,  it  gives  rise,  together  with  the  compound  ethers  (esters) 
to  the  corresponding  hydro-carbon,  so  that  the  first  transforma- 
tions which  the  alcohols  undergo  are  due  to  phenomena  of  dehy- 
dration. 
The  phenomena  of  isomerisation,  that'is,  changes  of  nature  with- 
out change  of  composition,  also  proceed  together  with  the  meta- 
morphosis of  the  odorous  matter.  Lastly,  the  alcohols  and  their 
ethers  are  actively  converted  into  their  oxidation  derivatives,  particu- 
larly when  the  inflorescences  appear,  in  which  organs  the  fixation 
of  oxygen  by  the  tissues  is  particularly  intense. 
Genesis  of  the  Odorous  Matters. — The  sum  of  my  researches,  and 
the  interesting  observations  of  M.  Hesse  lead  to  a  conception  of  the 
genesis  of  the  odorous  matters  in  the  plant.  A  large  number  of  the 
odorous  products,  very  diverse  in  their  functions  and  chemical 
structure,  are  produced  in  consequence  of  the  splitting  up,  with 
fixation  of  the  elements  of  water,  of  principles  called  glucosides.  It 
is  sufficient  to  admit  the  general  nature  of  such  a  mechanism  to 
arrive  at  a  satisfactory  explanation  of  the  facts  observed  with 
regard  to  the  formation  of  the  odorous  matters  and  their  appearance 
at  any  particular  point  of  the  vegetable  organism. 
It  seems  to  me  that  there  is  reason  to  believe  that  the  glucoside 
which  is  capable  of  yielding  the  essential  oil  is  formed  or  tends  to  be 
formed  in  the  green  portions.  Most  frequently,  this  glucoside 
immediately  encounters  the  conditions  of  environment  which  are 
favorable  to  its  decomposition,  and  then  the  essential  oil  appears 
in  the  green  portions  and  begins  to  circulate,  evolve  itself  and  play 
its  part.  It  may  even  happen  that  the  medium  is  so  favorable  to  the 
splitting  up  of  the  glucoside,  that  the  latter  can  never  be  formed; 
