AmbecUr'i^8arm'}  Growing  Medicinal  Plants  in  America.  871 
much  it  may  stimulate  vegetable  gardening  and  poultry  raising,  is 
not  applicable  to  the  growing  of  medicinal  plants.  The  U.  S.  P.  re- 
quirement for  dry  belladonna  herb  or  leaf  calls  for  an  assay  showing 
a  content  of  not  less  than  0.3  per  cent,  atropine  alkaloid.  Any  sub- 
stantial quantity  of  active  constituents  in  excess  of  this  prescribed 
minimum  should,  if  the  producer  is  aware  of  it,  be  credited  in  the 
price  paid  by  the  consumer.  The  small  producer  can  have  no  knowl- 
edge of  the  assay  value  of  his  product  unless  he  employs  the  services 
Fig.  7.    The  Institute  of  Industrial  Research,  Washington,  D.  C,  where  the 
drug  plants  are  analyzed  and  tested. 
of  a  chemical  laboratory.  Such  chemical  assays  require  special 
highly  paid  experts  in  order  to  obtain  accurate  results,  and  the  cost 
of  such  service  is  naturally  high.  In  the  opinion  of  the  writer,  un- 
less a  producer  is  able  to  hold  his  belladonna  to  an  assay  value  at 
least  twice  as  strong  as  the  U.  S.  P.  requirement  it  would  not  be 
worth  producing  at  all  under  American  conditions.  Such  high- 
potency  crude  drugs  can  be  obtained  only  by  the  application  to  the 
problem  of  trained  scientific  knowledge.  Plant  breeding  through 
seed  selection  and  a  knowledge  of  just  the  day  to  harvest  when  the 
