EFFECTS  OF  SOIL,  ETC.  ON  ACTIVE  PRINCIPLES  OF  PLANTS.  51 
tracted  from  the  leaves  of  the  plants  growing  on  the  original 
soil ;  it  yielded  larger  proportions  of  chlorides  and  sulphates. 
The  yield  of  ashes,  on  the  incineration  of  the  leaves  and  stalks, 
was  about  6*3  per  cent. 
The  analysis  of  the  soil  to  which  the  plants  were  removed  is 
given  in  Appendix  B. 
My  experiments  on  belladonna,  which  have  been  confined  to 
cultivated  specimens,  support  the  conclusion  that  very  marked 
differences  in  the  chemical  composition  of  the  soil  gives  rise  in 
a  corresponding  degree  to  differences  in  the  saline  constituents 
of  a  plant,  and  that  where  the  differences  are  but  slight,  no 
sensible  difference  is  produced  in  the  amount  of  mineral  matter 
contained  in  the  plant. 
From  the  seeds  of  these  plants  I  obtained  : — Albumen,  gum, 
inulin,  phosphate  of  soda,  nitrate  of  potash,  chloride  of  potassi- 
um, sulphate  of  potash,  an  acid  salt  of  atropia,  malic  and  mucic 
acids,  chlorophyll,  and  a  peculiar  principle,*  similar  to  chloro- 
phyll. 
Hot  water  extracts  a  very  large  proportion  of  phosphates 
and  sulphates,  which  are  readily  deposited  in  a  crystalline  form. 
At  different  seasons  the  organic  salts  are  found  to  offer  the 
greatest  variation ;  many  are  detected  only  after  the  fall  of  the 
flower.  I  could  not  detect  mucic  acid  in  any  part  of  the  bella- 
donna plants  except  the  seeds.  The  presence  of  malic  acid  in 
stramonium  seeds  increases  after  the  fall  of  the  flower,  but  is 
*This  principle,  I  find,  exists  in  the  seeds  of  all  plants  on  which  I  have 
operated  ;  it  differs  from  chlorophyll,  first,  in  its  solutions  not  becoming 
yellow  on  exposure  to  the  air,  and  secondly,  its  insolubility  in  hydrochloric 
acid.  It  may  be  isolated  by  digesting  the  alcoholic  extract  in  a  mixture 
of  hydrochloric  acid  and  ether,  and  separating  the  supernatant  solution, 
and  allowing  it  to  evaporate  spontaneously.  It  then  remains  as  a  soft, 
oily  substance,  possessing  the  odor  of  the  plant  from  which  it  is  extracted. 
M.  Fremy  has  announced  to  the  Academy  of  Sciences  that  he  has  found 
a  substance  in  the  leaves  of  plants  which  he  regards  as  a  modification  of 
chlorophyll,  and  from  its  general  properties  I  am  inclined  to  think  that  it 
is  identical  with  what  I  have  found  in  the  seeds  and  seed-vessels,  but  it 
certainly  performs  a  different  function  here  to  that  suggested  by  M.  Fre- 
my with  regard  to  leaves. 
