342  Strophanthus  Seed  of  Commerce.  {Am'juciy^arn1' 
THE  STROPHANTHUS  SEED  OF  COMMERCE.1 
By  E.  M.  Holmes,  F.L.S., 
Curator  of  the  Museum  of  the  Pharmaceutical  Society 
The  difficulty  of  obtaining  Strophanthus  seed  of  uniform  charac- 
ter, agreeing  with  the  description  given  in  the  "  Addendum  "  to  the 
Pharmacopoeia,  is  well  known.  Except  by  purchasing  the  follicles, 
it  is  now  almost  impossible  to  procure  unmixed  seed.  This  diffi- 
culty has  apparently  arisen  from  a  supposition  on  the  part  of  the 
collectors  that  all  kinds  of  Strophanthus  possess  the  same  proper- 
ties, and  on  the  part  of  merchants,  that  Strophanthus  seeds  Trom 
any  part  of  Africa  would  sell.  At  all  events,  there  is  circumstantial 
evidence  to  prove  that  the  Strophanthus  seed  of  commerce  very 
frequently  consists  of  a  mixture  of  seeds  derived  from  various 
species.  When  the  seed  is  sown,  it  gives  rise  to  young  plants,  pos- 
sessing different  leaves,  etc.,  and  evidently  belonging  to  different 
species.  The  seeds  themselves  also  differ  in  external  characters. 
In  many  cases,  also,  seeds  presenting  a  great  similarity  in  color  and 
general  appearance  possess  different  cell  contents  and  a  different 
active  principle.  In  the  hope  of  promoting  the  importation  of  a 
uniform  product  and  of  enabling  pharmacists  to  ascertain  with 
greater  accuracy  than  heretofore  the  genuineness  and  quality  of  the 
seeds  they  employ,  I  propose  to  give  a  resume  of  what  is  known 
concerning  this  powerful  drug  and  its  botanical  sources. 
The  species  of  Strophanthus  are  as  yet  very  imperfectly  known. 
The  two  chief  centres  of  distribution  of  the  plants  of  this  genus 
are  tropical  Africa  and  Southeastern  Asia.  In  the  "  Genera  Plan- 
tarum  "  (Benth.  and  Hook,  f.,  vol.  ii,  p.  714)  the  number  of  species 
is  given  as  eighteen,  but  in  a  recent  revision  of  the  genus  by  Dr.  F. 
Pax  ("Engler  Jahrbucher,"  1892,  pp.  362-386)  seven  new  species 
have  been  added  to  the  list,  of  which  six  are  African  and  one 
Malayan.  The  distribution  of  the  species  is  given  as  follows : 
West  Africa.  Senegambia,  S.  laurifolius,  S.  sarmentosus. 
Sierra  Leone,    5.  sarmentosus,  S.  hispidus, 
Niger  Territory.    S.  scaber. 
Cameroons.    S.  Preussii,  S.  BullenianuS. 
Gaboon.    5.  Bullenianus,  S.  gracilis. 
Congo.   vS.  Ledieni. 
1  Phar.  Jour,  and  Trans.,  April  22  and  May  13,  pp.  868  and  927-931. 
