ON  THE  BOTANICAL  SOURCE  OF  BALSAM  OF   PERU.  411 
LETTER  TO  THE  EDITOR  ON  THE  BOTANICAL  SOURCE  OF 
BALSAM  OF  PERU. 
By  Daniel  Hanbdry,  F.  L.  S. 
London,  August  2d,  1860. 
Plough  Court,  Lombard  Street. 
My  dear  Sir, — I  am  extremely  obliged  to  you  for  sending  me 
that  portion  of  the  last  number  of  the  American  Journal  of 
Pharmacy  which  contains  the  two  communications  on  the  Bal- 
sam of  Peru.  The  subject  is  one  which  I  have  long  studied, 
and  in  which  I  have  taken  much  interest,  especially  since  the 
death  of  my  old  preceptor,  Dr.  Pereira. 
Dr.  Carson's  paper  is  valuable  from  containing  a  figure  (the 
first  that  has  been  published)  of  the  flowers  of  the  Balsam  of 
Peru  tree  ; — but  on  the  other  hand  I  am  concerned  to  think  the 
author  has  not  had  access  to  some  direct  information  on  the 
subject.  Since  Pereira's  paper  was  published,  we  have  learnt 
much  from  other  sources  respecting  the  botany  of  Myrosper- 
mum  and  Myroxylon.  The  Myrospermum  of  Sonsonate',  (Pe- 
reira in  Pharm.  Journal,  Dec.  1850,)  has  been  admitted  a 
distinct  species,  and  described  as  such  by  Boyle,  under  the  name 
of  M.  Pereira  (Boyle,  Manual  of  Mat.  Med.,  ed.  2,  1853,  p. 
414.) 
In  addition  to  this,  Dr.  Klotzsch,  of  Berlin,  has  published  in 
the  Bonplandia,  15th  Sept.,  1857,  an  elaborate  enumeration  of 
all  the  species  of  Myroxylon  and  Myrospermum — the  former  8  in 
number,  the  latter  3.  Boyle's  species  is  transferred  to  the  genus 
Myroxylon,  under  the  name  of  M.  Pereira,  Kl.,  and  maintained 
by  Dr.  Klotzsch  as  quite  distinct  from  M.  peruiferum,  Mutis  et 
Linn.  fil.  As  my  own  herbarium  includes  small  specimens  of 
all  the  species  enumerated  by  Dr.  Klotzsch,  and  I  have  care- 
fully examined  the  specimens  that  are  contained  in  the  herbaria 
of  Kew,  the  British  Museum,  and  the  Jardin  des  Plantes  in 
Paris,  I  may  be  allowed  to  offer  an  opinion  in  confirmation  of 
Dr.  K's.  view,  that  these  species  are  distinct.  At  the  same 
time  I  must  express  the  opinion  that  several  of  Dr.  Klotzsch's 
species  are  founded  on  very  inadequate  materials,  and  that  much 
remains  to  be  done  before  we  arrive  at  a  satisfactory  knowledge 
of  the  plants  in  question. 
I  hope  Dr.  Carson  will  continue  in  communication  with  Dr* 
