16 
The  Japanese  Peppermint  Plant. 
j  Am.  Jour.  Pharm. 
1      Jan.,  1883. 
Candolle's  "  Prodromus  the  leaves  being  stalked,  ovate  lanceolate, 
and  the  hairs  on  the  stems  and  pedicels  reflexed,  those  of  the  calyx 
being  erecto-patent,  and  those  of  the  upper  surface  of  the  leaf  appressed, 
the  calyx  being  bell-shaped  with  acute  lanceolate  or  narrowly-triangu- 
lar teeth.  The  Chinese  plant  differs  from  the  Japanese  one  in  the 
leaves  being  narrower  in  proportion  to  their  length  and  in  the  calyx 
teeth  being  shorter  and  more  broadly  triangular.  In  outline,  the 
leaves  of  both  plants  taper  more  to  the  base  and  have  a  longer  petiole 
than  the  English  forms  of  31.  arvensis,  coming  very  near  to  M.  cana- 
densis in  this  feature.  The  latter  plant  however,  has  spreading  hairs 
on  the  stem.  The  Chinese  plant  appeared  to  so  nearly  resemble 
3L  canadensis,  var.  glahrata,  that  I  applied  to  Professor  Asa  Gray  for 
specimens  of  that  species  for  comparison.  The  specdmens  of  M.  cana- 
densis which  he  kindly  forwarded  to  me  were  derived  from  different 
localities  in  the  United  States,  and  varied  considerably  in  taste  and 
appearance,  some  having  the  flavor  of  pennyroyal,  others  that  of 
viridis,  and  others  again  that  of  peppermint,  in  a  feeble  degree.  The 
specimen  having  a  peppermint  flavor  is  labeled  M.  canadensis,  var. 
glahrata;  it  has  reflexed  hairs  on  the  stem,  and  differs  from  the  typical 
plant  in  having  more  triangular  and  shorter  calyx  teeth,  which,  as 
well  as  the  petioles,  have  erect  hairs ;  in  fact,  it  appears  in  every 
respect  to  be  the  same  plant  as  that  grown  at  Canton.  It  is  not  sur- 
prising, however,  to  find  Japanese  or  Chinese  plants  extending  to 
North  America. 
It  appears,  then,  that  there  are  two  plants  possessing  a  widely  differ- 
ent taste  and  both  referred  to  31.  arvensis,  var.  Javanica,  by  botanists. 
This  might  lead  to  confusion  if  the  Chinese  or  Japanese  peppermint 
plants  ever  came  into  demand  for  purposes  of  cultivation,  unless  a 
special  name  be  given  to  the  form  which  possesses  the  peppermint 
flavor,  even  although  it  does  not  possess  characters  sufficiently  definite 
to  separate  it  from  31.  arvensis.  The  mints  are  well  known  to  form 
an  uninterrupted  series  of  plants  which  it  is  difficult  to  separate  into 
species.  Deeming  it  advisable,  therefore,  before  giving  it  a  name,  to 
consult  those  botanists  who  have  critically  studied  the  mints,  speci- 
mens of  the  Japanese  peppermint  plant  were  forwarded  to  several 
authorities  on  the  genus,  and  the  following  opinions  have  been 
expressed  :  Mr.  J.  G.  Baker,  of  the  Kew  Herbarium,  considers  it  to 
be  a  form  of  3Ientha  scdiva,  Sm.  (It  may  be  here  remarked  that  this 
form,  as  recognized  by  Hooker  and  Babington  in  their  "British 
