460  Effect  of  Altitude  on  Red  Bark         { "^""sS'isss ™' 
the  Ledgeriana  turn  red  in  fading,  which  is  said  by  Mr.  Ledger  to  be 
characteristic  of  his  "  rojo {roxo)  at  the  flowering  season,  from  which 
it  derives  its  name  red.^^ 
They  are  more  deKcately  formed  than  the  others  I  have  named,  and 
more  easily  damaged  by  direct  sunlight.  As  night  approaches,  the 
top  leaves  gradually  change  their  position,  approaching  each  other  so 
as  in  some  cases  almost  to  fold  together.  This  is  well  shown  in  a  fine 
plant  of  true  Ledgeriana  which  I  have  from  Darjeeling,  and  also  in 
the  more  flourishing  of  my  plants  from  Ceylon.  I  do  not  notice  the 
same  in  the  verde  from  Mr.  Christy's  Bolivian  seed,  of  which  the 
leaves  are  more  robust,  but  the  above  features  are  not  confined  to  the 
"rojo.^^ 
These  peculiarities  would  scarcely  be  seen  unless  the  plants  were  well 
developed  under  glass,  but  once  observed  it  is  impossible  to  forget  or 
to  confuse  these  rich  varieties  of  Calisaya  (which  I  described  and 
figured  as  such  from  well  ascertained  specimens  sent  by  M.  Moens) 
with  the  plant  described  and  figured  by  Dr.  Trimen  as  "  C.  Ledgeriana, 
Moens,''  and  which  I  should  call  C.  micrantha,  var.  Calisayoides.  Dr. 
Trimen  had  not  the  opportunity  of  comparing  the  plates  drawn  by 
Fitch,  in  my  "  Quinology,"  with  those  in  the  Journal  of  Botany  ;  but 
the  distinction  is  most  evident,  as  I  have  endeavored  to  demonstrate  to 
the  Linnean  Society.  My  figures  of  C.  Calisaya,  var.  Ledgeriana,  are 
from  trees  yielding  respectively  (PI.  IV.)  9*06,  (PI.  Y.)  9-90,  and  (PL 
VI.)  9*97  per  cent,  of  quinine  and  the  fruit-bearing  branch  10'90 
(same  plate).    See  the  account  of  my  herbarium,  pp.  58-66. 
The  "  rojo  "  (roxo),  or  C.  Calisaya,  var.  Ledgeriana,  is  the  queen  of 
all  the  Cinchonas;  but  certainly  possesses  a  delicate  organization  which 
makes  the  cultivation  difficult.  The  "  verde,"  as  being  a  quick  grow- 
ing tree,  flourishing  at  lower  elevation,  is  found  in  Bolivia  more  pro- 
fitable to  cultivate  than  the  "  morada,"  although  the  latter  is  richer  in 
percentage  of  quinine.  I  do  not  think  that  the  Ledgeriana  is  culti- 
vated in  Bolivia,  but  another  sort  of  rojo"  is  extensively  planted  in 
Coroico,  in  the  Yungas  of  Bolivia.  ''This  is  not  so  good  as  the  Cau- 
polican  rojo."  It  is  the  Colorada  naranjada,  or  orange  peel  red,  only 
known  to  me  by  the  bark,  which  has  a  character  peculiarly  its  own. 
The  bark  of  the  Ledgeriana  is  most  characteristic.  It  is  thick  and 
composed  almost  entirely  of  cellular  tissue ;  quite  contrasted  with  that 
of  the  "  verde,"  which  bears  the  stamp  of  more  vigorous  growth  and 
