Am.  Jour.  Pharm. 
June,  1894. 
Economic  Botany. 
285 
about  three  centuries  ago,  with  the  work  of  the  Florentine,  Caesal- 
pinus,  but  it  made  only  slow  progress  until  about  a  century  later, 
when  the  Englishman,  John  Ray,  in  his  Methodus  Plantarum,  laid 
the  first  really  rational  basis  for  plant  classification.  From  this 
time  on,  through  the  work  of  Tournefort,  Linnaeus,  Jussieu,  A.  P. 
De  Candolle,  Endlicher,  Lindley,  Hooker,  Bentham,  Alphonse  De 
Candolle  and  Gray,  systematic  botany  has  made  rapid  and  splendid 
progress. 
Necessarily,  owing  to  the  later  development  of  the  compound 
microscope  and  that  of  chemical  science,  the  growth  of  physiologi- 
cal botany  was  more  retarded.  Although  in  ancient  times  some 
crude  notions  existed  about  the  sexuality  of  plants,  the  functions  of 
stamens  and  pistils  do  not  appear  to  have  been  understood  until 
Grew  explained  them  in  1676.  From  this  time  until  1823  no 
great  progress  was  made  in  this  branch.  In  this  year,  Amici  dis- 
covered the  pollen  tubes,  and  a  little  later  Robert  Brown  traced 
them  to  the  nucellus  of  the  ovule.  Since  then  the  embryology  of 
plants  has  made  rapid  strides  through  the  labors  of  such  men  as 
Schleiden,  Mohl,  Naudin,  Hofmeister,  Strasburger,  Baillon,  Bornet, 
Decaisne,  Tulasne,  and  last,  but  not  least,  Darwin. 
The  latter's  work  on  cross-fertilization  not  only  opened  up  a 
wholly  new  field  in  connection  with  the  subject  of  sexual  physiology, 
but  his  works  on  climbing  plants  and  on  insectiverous  plants,  as 
well  as  his  earlier  work,  in  which  he  promulgated  his  doctrine  of  the 
origin  of  species  by  natural  selection,  have  given  a  tremendous 
impulse  to  other  branches  of  vegetable  physiology. 
It  is  true  that  this  development  of  which  we  have  just  been 
speaking  has  mainly  been  on  the  purely  scientific,  rather  than  on 
the  utilitarian  side,  at  least  until  quite  recently.  But  a  science  pur- 
sued for  its  own  sake,  with  a  pure  love  of  knowledge  for  its  motive, 
and  regardless  of  ulterior  results,  could  not  but  lead  to  important 
practical  applications,  and  so  it  has  been  in  this  instance.  Espe- 
cially have  the  developments  in  vegetable  physiology  found  abun- 
dant applications.  There  is  no  branch  of  economic  botany  that  has 
not  received  tremendous  impetus  from  the  researches  of  such  men 
as  Sachs,  Strasburger  and  Darwin. 
The  researches  of  these  men  seem  far  enough  from  what  is  ordi- 
narily called  practical,  nevertheless  they  have  served  as  a  leaven,  to 
leaven  the  whole  lump  of  botany,  practical  as  well  as  theoretical ; 
