^"^Nov"'^i882''^"'' }      Aconitum  Napellus  and  other  Species.  557 
prompt  and  reliable  action  is  of  the  utmost  consequence.  The  cluef 
difficulty  in  making  such  a  preparation  is  in  obtaining  the  typical 
variety  of  the  right  species.  De  Candolle  describes  twenty-nine  vari- 
eties of  the  official  species,  Aconitum  Napellus,  but  whetlier  all  these 
forms,  which  possess  the  same  specific  botanical  characters  in  common,, 
have  the  same  chemical  constituents,  and  whether,  like  isomorphic 
crystals  and  isomeric  bodies  in  general,  they  have  a  different  physiolo- 
gical action,  is  very  difficult  to  ascertain,  seeing  that  it  is  by  no  means 
easy  to  identify  them,  for  the  following  reasons  :  First,  because  a  com- 
plete series  of  the  members  of  the  genus  is  hardly  to  be  found  for 
reference  in  any  botanical  garden  or  museum ;  secondly,  because  the 
varieties  sold  by  florists  are  not  always  carefully  named ;  and  thirdly^ 
because  they  cannot  be  procured  in  sufficient  quantities  for  purposes  of 
chemical  investigation. 
Moreover,  botanists  are  not  agreed  as  to  the  forms  which  should  be 
placed  under  each  species.  Steudel  enumerates  about  eighty  which 
have  been  grouped  under  A.  Napellus  by  different  botanists.  The 
aconites  are  so  closely  allied,  and  the  varieties  run  so  much  into  one 
another,  like  the  willows,  brambles,  roses,  mints  and  cinchonas,  that 
even  De  Candolle  has  placed  the  same  plant  under  two  varieties.  Pro- 
fessor Maximowicz,  who  has  paid  considerable  attention  to  the  species 
occurring  in  Japan,  remarks,  in  a  recent  letter :  The  genus  Aconitum 
is,  botanically  speaking,  a  most  difficult  one,  not  one  characteristic 
holding  its  own  from  species  to  species.  It  is  a  matter  of  personal 
opinion  whether  you  accept  a  dozen  species  in  all,  while  another  thinks 
to  separate  thrice  the  number.  I  have  observed  them  in  Mandshuria 
and  Japan  very  assiduously,  and  have  despaired  of  finding  well-defined 
species,  for  there  will  arise  intermediate  forms  between  such  as  in  most 
cases  are  thoroughly  different.  One  would  think  these  were  numerous 
hybrids,  but  they  are  as  freely  seed-bearing  as  the  various  hybrid  aqui- 
legias  used  to  be." 
Although  it  is  almost  impossible  to  define  accurately  in  botanical 
terms  the  different  aconites,  it  seemed  to  me  worthy  of  inquiry  whether 
those  available  for  ])harmaceutical  purposes  might  not  be  characterized 
sufficiently  for  all  ])ractical  purposes.  It  is  well  known  that  the  Japa- 
nese ])cppermint  plant,  although  botanically  it  offers  no  character  to 
scpaiate  it  from  Mentlia  saliva,  is  already  distinguishable  by  taste,  and 
it  is  tlierefore  natural  to  suppose  that  the  different  forms  of  aconite 
might  be  distinguished  to  a  certain  extent  in  the  same  way.  Experi- 
