40  The  Apocynacece  in  Materia  Medica.    {  January 5m' 
by  Polaillon  and  Carville  and  the  chemical  investigations  by  Gallois 
and  Hardy,  Catillon,  Arnaud,  etc.,  these  seeds  can  not  yet  be 
referred  with  certainty  to  any  species  botanically  determined. 
According  to  M.  Franchet,  it  is  a  fact,  however,  remarkably  inter- 
esting :  that  in  all  the  Strophanthus  with  glabrous  seeds  (all  the 
Asiatic  species  are  in  this  class),  there  exists  a  constant  relation 
between  the  absence  of  all  villosity  and  the  length  of  the  point 
that  terminates  the  anther.  Now  among  the  numerous  African 
Strophanthus,  two  only  present  this  character  of  the  anthers,  the 
S.  gratus  Franch.  and  >S\  Tholloni  Franch.  which  inhabit  precisely 
the  region  of  the  origin  of  5.  glaber.  According  to  Thollon  this 
second  species  bears  at  Gaboon  the  name  of  Onaie.  It  is  thus 
allowable,  with  Franchet,  to  attribute  this  seed  to  one  or  the  other 
of  these  plants,  provisionally  and  the  rather  to  gratus  which  is 
likewise  from  the  Gaboon,  while  the  .S.  Tholloni  is  from  the  regions 
of  the  rapids  of  the  Ogoway  consequently  more  to  the  East. 
The  S.  gratus  Franch.  {Roupellia  grata  Wall  et  Hook.,  Nerium 
guineense  Brongn.,  etc.)  is  a  small  tree,  according  to  Griffon  du 
Bellay,  but  more  probably  a  liane.  The  plant  inhabits  Guinea,  the 
Gaboon  and  Sierra  Leone,  whence  it  was  introduced  into  culture  by 
Whitfield  under  the  name  5.  Stanley  anus. 
The  S.  Tholloni  Franch.  is  probably  the  species  of  which  the 
fruits  were  sent  by  Thollon  containing  seeds  very  analogous  to  those 
of  the  S.  glaber.  It  is  a  long  liane  of  western  Africa  inhabiting  the 
French  region  of  the  Congo,  especially  the  course  of  the  upper 
Ogoway  and  the  Cameroon,  and  its  extent  may  be  quite  far  towards 
the  centre  of  the  continent.  The  lobes  of  the  corolla  are  short  and 
sharp  in  the  vS.  Tholloni  and  nearly  round  in  S.  gratus. 
The  S.  glaber  serves  for  the  fabrication  of  the  arrow  poison  in 
this  district.1  For  a  long  time  the  seeds  were  confounded  with  those 
of  S.  hispiduSy  from  which  they  may  be  easily  distinguished. 
1  The  bark  and  leaves  are  poisonous,  but  less  so  than  the  seeds.  To  obtain 
one  kilogramme  of  the  seed  150  pods  must  be  collected. 
It  is  this  seed  which  is  employed  for  the  kombe poison.  The  seeds  deprived 
of  their  awn,  are  beaten  between  two  stones,  and  the  paste  worked  up  with  a 
knife  into  a  creamy  consistence  by  the  addition  of  a  little  water  or  certain  veg- 
etable juices,  and  becomes  a  red  color  from  exposure  to  air.  This  paste  is 
applied  to  the  points  of  the  arrows  or  they  are  rolled  in  the  substance,  to  which 
is  previously  added  some  adhesive  ingredient  (the  mucilaginous  bark  of  a 
Tiliaceue,  the  latex  of  a  Euphorbium  rich  in  caoutchouc,  the  juice  of  the 
