420       PRESENT  STATE  OF  OUR  KNOWLEDGE  OF  CINCHONA. 
should  be  kept  carefully  select  in  commerce,  and  consequently 
the  rate  of  produce  in  alkaloid,  from  such  mixed  parcels  of  bark, 
falls  below  that  of  the  genuine  tree  ;  but  Mr.  Howard  has  satis- 
fied himself,  by  the  examination  of  carefully  chosen  specimens 
of  Calisaya,  of  the  existence  of  alkaloid  equal  to  five  per  cent., 
and  in  one  or  two  specimens  even  seven  or  eight  parts  in  a  hun- 
dred, of  sulphate  of  quinine.  This  is  more  than  double  the  pro- 
duct assigned  by  the  late  M.  Delondre,  whose  "  Quinologie  "  he 
regards  as  a  very  valuable  repository  of  knowledge,  although  (as 
is  always  the  case)  subject  to  some  little  correction. 
The  average  produce  of  Calisaya  bark  in  quinine,*  though 
falling  very  far  short  of  the  exceptionally  fine  specimens  before 
mentioned,  is  still  considerably  above  that  obtained  by  M.  De- 
lmdre,  and  the  product  in  cinchonine  less  by  two-thirds  than  he 
states,  only  it  may  be  that  he  includes  the  cinchonidine  in  the 
same  category.  These  observations  seem  of  importance  in  refer- 
ence to  the  cultivation  of  the  species  in  India.  It  must  not  be 
supposed  that  the  large  products  obtained  by  Dr.  De  Vrij  and 
Mr.  Howard  from  the  Cinchona  succirubra  grown  by  M'lvor,  are 
the  measure  of  the  superiority  of  this  species  over  the  Calisaya. 
In  the  writer's  opinion,  the  reverse  is  the  truth,  and  though,  from 
some  cause,  equal  success  has  not  been  attained  with  the  latter 
in  the  East  Indies,  he  does  not  at  all  despair  of  seeing  the  Cali- 
saya reassume  there  its  rightful  supremacy  as  the  queen  of  all 
quinine-growing  species. 
He  is  the  more  confirmed  in  this  hope,  because  the  Calisaya, 
though  found  so  delicate  in  India,  is  growing  luxuriantly  under 
double  glass  in  Mr.  Howard's  stoves, — one  raised  from  seed  sent 
by  Sir  R.  Murchison  to  Kew  in  Mayr  1864,  f  two  or  three  inches 
in  height  when  first  planted  out  in  October,  1864, — having,  in 
*  Not  contained  in  the  bark  as  Sulphate,  as  Delondre  and  Bouchar- 
dat's  work  might  lead  the  reader  to  suppose. 
f  Dr.  Hooker  obligingly  traced  out  the  history  of  this  plant  by  applica- 
tion to  Sir  R.  Murchison,  who  says  :  "  The  cinchona  seeds  I  sent  you  in 
1864  were  brought  home  by  Mr.  David  Forbes,  a  great  explorer  of  the 
Peruvian  and  Chilian  Andes.  I  know  that  he  attached  some  value  to 
these  seeds,  which  he  told  me  were  from  trees  of  the  very  first  quality  in 
their  bark  and  fructification." 
