THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
JULY,  1887. 
ON  JALAP  RESIN  AND  JALAPIR 
By  John  M.  Maisch. 
Read  before  the  Pennsylvania  Pharmaceutical  Association,  June  16. 
Active  principles  or  characteristic  constituents  isolated  from  plants 
are  usually  designated  bynames  derived  either  from  the  generic  or 
specific  botanical  name  of  the  plant ;  in  some  cases  it  has  been  found 
more  convenient  to  start  from  the  popular  name  by  which  the  plant  or 
its  useful  part  is  known ,  either  in  its  native  country,  or  in  the  country 
in  which  the  investigation  has  been  made.  The  same  rule  holds  also 
good  for  pharniacopceial  and  other  medicinal  drugs.  If  we  apply  this 
rule  to  the  tuberous  jalap  root  of  Mexico,  we  have,  in  the  first  place, 
the  officinal  names  Jalapa  and  Radix  jalapce,  or  Tuberajalapce,  by  which 
it  has  been  admitted  into  the  different  pharmacopoeias,  and,  on  the 
other  hand,  quite  a  number  of  botanical  names  have  been  given  to  the 
plant,  which  is  Convolvulus  officinalis,  Pelletan,  Conv.  Jalapa,  Schiede, 
(not  Lin.),  Conv.  Purga,  Wenderoth,  Ipomcea  Purga,  Hayne,  Ip.  Jal- 
apa, Nuttall,  (not  Pursh),  Ip.  Schiedeana,  Zuccarini,  Exogonium 
Purga,  Beniham,  and  Exog.  Jalapa,  Baillon.  The  drug  is  known  in 
Mexico  as  purga,  also  as  limoncillo  and  jalapa  hembra,  or  female 
jalap.  The  most  characteristic  name  for  the  chief  medicinal  principle 
of  this  drug  would  evidently  be  jalapin,  while  purgin  derived  from 
the  Mexican  vernacular  is  obviously  unsuitable.  The  former  name 
has  been  used  for  the  decolorized  resin  in  older  medical  and  pharma- 
ceutical works,  and  is  occasionally  still  met  with  for  the  so-called 
resinoid,  which  is  simply  the  resin,  more  or  less  purified  by  washing 
with  water,  by  repeated  precipitation  from  alcohol,  or  by  treatment  of 
its  alcoholic  solution  with  animal  charcoal.  In  chemistry,  however, 
jalapin  is  a  totally  different,  though  an  analogous  compound. 
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