Am.  Jour.  Pharm. 
June,  1894. 
Economic  Botany. 
289 
As  respects  the  physiology  of  medicinal  plants  and  particularly 
that  important  branch  of  it  which  relates  to  the  increase  and  im- 
provement of  the  yield  of  medicinal  constituents,  nothing  more  en- 
couraging may  be  said  than  that  it  is  sadly  neglected,  the  schools, 
even  those,  of  pharmacy,  having  ignored  the  subject  altogether. 
In  two  or  three  lines  only  does  this  department  appear  to  have 
kept  abreast  of  agricultural  and  horticultural  botany.  This  is,  per- 
haps, the  case  with  vegetable  histology,  and  it  is  decidedly  the  fact 
with  the  investigation  of  the  chemical  constituents  of  plants. 
Since  the  German  apothecary,  Sertiirner,  in  1 8 17,  announced  the 
discovery  and  isolation  of  the  first  known  alkaloid,  morphine,  there 
has  been  in  our  profession  increasing  activity  in  this  line  of  research, 
and  never  has  there  been  such  widespread  interest  in  the  subject  as 
at  present.  To  the  credit  of  this  college  it  should  be  said  that  it 
has  done  its  full  share  of  work  of  this  character. 
But  what  has  been  done — valuable  as  it  is — is  only  an  infinitesi- 
mal part  of  what  remains  to  do.  That  may  not  be  wholly  true 
which  Emerson  suggests,  that  every  weed  is  a  plant,  the  uses  of 
which  we  do  not  yet  understand,  but  it  is  safe  enough  to  say  that 
amongst  the  175,000  or  thereabouts  of  plant  species  that  have  been 
described  and  named,  and  the  possibly  as  many  more  that  await 
discovery,  there  are  many  times  the  number  we  know  of  at  present 
that  are  capable  of  serving  mankind  in  a  useful  way.  We  know  not 
what  value  may  lie  even  in  many  of  the  despised  weeds  about  us, 
to  be  revealed  by  careful  chemical  research.  Every  day  we  are  dis- 
covering new  vegetable  principles  and  discovering  new  uses  for  old 
ones.  If  such  wealth  as  the  aniline  dyes  came  from  such  an 
unpromising  and  apparently  worthless  substance  as  coal  tar,  what 
may  we  not  hope  from  the  many  thousands  of  plants  that  are  scarcely 
known  to  us  yet,  except  by  name  ?  Of  the  flowering  plants  that 
remain  to  be  discovered  we  cannot  count  on  more  than  from  10,000 
to  12,000  species,  but  these  give  great  promise,  because  they  lie 
mostly  in  the  great  central  regions  of  Africa  and  Asia,  where  plants 
of  much  potency  may  be  expected  to  occur. 
The  least  explored  botanical  fields  are  those  of  fungi  and1 
bacteria.  How  many  species  of  these  groups  remain  to  be 
described  it  is  impossible  even  to  guess.  We  can  only  say  that  the 
number  is  vast,  and  possibly  when  all  are  known  may  be  found  to< 
exceed  that  of  all  other  plants  put  together.    The  probabilities  of 
