Ami/arch.^898!m'}  True  and  False  Cactus  Grandiflorus.  155 
chemistry  of  Opuntia  decumana,  Haworth,  not  of  Cereus  (Cactus) 
grandiflorus,  Miller.  We  owe  the  unearthing  of  this  blunder  to  the 
learned  Curator  of  the  Pharmaceutical  Society's  Museum  in  London, 
Mr.  E.  M.  Holmes.  Mr.  Holmes  investigated  this  subject  last  sum- 
mer, and  communicated  with  me,  and  I  sent  him  a  specimen  of  the 
drug  we  had  worked  with,  and  at  once  the  fallacy  was  discovered. 
He  has  written  an  article  on  the  subject  of  Cereus  and  Opuntia  in 
the  Pharmaceutical  Journal  of  August  21,  1897.  The  pharma- 
cology of  my  article  in  the  number  of  the  Practitioner  already 
quoted  is  really  the  the  pharmacology  of  Opuntia,  not  of  Cereus. 
The  question  of  therapeutical  action  does  not  concern  a  company 
of  pharmacists,  but  it  is  almost  necessary  for  me  to  refer  shortly  to 
this  aspect  of  the  subject.  The  therapeutic  observations  were  made 
from  specimens  of  both  Cereus  and  Opuntia,  and  also  from  pills 
prepared  from  the  formula  of  Mr.  T.  W.  Sultan.  Each  pill  contains 
Tor  §ram  °f  extract  of  genuine  Cereus.  Mr.  Sultan  does  not  say 
in  his  pamphlet  whether  this  preparation  is  an  alkaloid,  or  a  resin, 
or  a  glucoside  ;  he  merely  calls  it  the  active  principle.  After  all, 
then,  my  practical  results  are  not  much  affected,  if  affected  at  all,  by 
my  pharmacological  and  botanical  blunders.  I  am  not  alone  in  my 
experience,  for  I  have  had  sent  me  from  various  sources  samples  of 
tincture,  labelled  Cactus  grandiflorus,  but  which  were  preparations  of 
Opuntia,  and  yet  medical  men  had  assured  the  senders  that  they 
possessed  the  virtues  ascribed  to  the  genuine  drug.  Since  the 
publication  of  my  article  in  the  Practitioner  I  have  had  opportunities 
of  carefully  testing  genuine  Cereus  alongside  strophanthus  and  our 
old  friend  foxglove,  and  I  have  come  to  the  conclusion  that  Cactus, 
whether  genuine  or  spurious,  is  worthless,  and  should  be  discarded 
by  both  pharmacist  and  physician.  Why  should  Opuntia  have  been 
so  widely  sold  for  Cereus  ? 
From  the  fact  that  we  obtained  spurious  specimens  from  so  many 
sources,  we  must  conclude  that  Opuntia  has  been  widely  distributed. 
On  first  consideration  we  are  strongly  tempted  to  blame  the  drug 
merchants  for  imposing  a  spurious  drug  on  the  buyer.  I  do  not 
share  this  view.  I  believe  the  mistake  arises  largely  owing  to  the 
carelessness  of  botanists  in  often  calling  Cereus  by  the  name  Cactus. 
I  do  not  know  whether  Opuntia  vulgaris,  Miller,  is  another  name 
for  Opuntia  decumana,  Haworth,  but  I  do  know  that  Opuntia  vul- 
garis is  also  known  as  Cactus  opuntia,  Linne.    Here,  then,  may  be 
