406 
Plant  Morphology  and  Taxonomy. 
f  Am.  Jour.  Pharm. 
I  September,  1905. 
cells  and  showed  by  his  studies  on  the  starch  grain  and  cell-wall 
how  intricate  and  far-reaching  the  problems  of  morphology  are. 
Von  Mohl's  studies  on  the  nature  and  distribution  of  tissues  in 
plants,  together  with  the  work  of  Hanstein  and  others,  laid  the 
foundation  upon  which  De  Bary  in  1877,  together  with  his  own 
researches,  wrote  his  book  "The  Comparative  Anatomy  of  the 
Vegetative  Organs  of  the  Phanerogams  and  Ferns,"  which  is  still 
a  recognized  authority. 
It  was  during  these  same  years  that  the  series  of  investigations  on 
the  mode  of  reproduction  in  plants  was  begun,  which  culminated  in 
the  brilliant  results  obtained  by  Hofmeister,  and  which  has  been 
carried  on  with  increasing  interest  even  to  the  present  time.  The 
work  begun  by  Brown  on  the  mode  of  fertilization  in  the  Phaner- 
ogams was  carried  to  completion  by  Amici  in  1846.  The  work  of 
Bischoff,  Mirbel,  Unger  and  Nageli  on  the  male  sexual  organs  in 
the  Archegoniatae  was  supplemented  by  that  of  Hofmeister,  who 
discovered  the  archegonia  or  female  organ  of  reproduction  and  who 
thus  gave  the  first  authentic  description  of  the  mode  of  fertilization 
in  the  lower  plants.  His  work  also  brought  to  light  one  of  the 
most  interesting  discoveries  in  the  whole  realm  of  botanical  science 
— namely,  the  alternation  of  generation  in  plants.  Hofmeister 
extended  his  studies  to  the  Conifers  and  Angiosperms,  and  thereby 
not  only  established  the  affinity  between  these  two  groups,  but 
showed  their  genetic  relation  to  the  Pteridophytes,  and  thus  con 
tributed  a  series  of  the  most  important  researches  to  what  has  now 
come  to  be  known  as  phylogenetic  morphology,  or  the  study  of 
the  origin  and  relation  of  the  various  plant  groups. 
During  the  period  between  1850  and  i860  the  discovery  of  the 
alternation  of  generation  in  plants  was  further  confirmed  by  Hof- 
meister's  work  on  the  Equisetaceae,  Isoetes,  etc.,  and  by  the  investi- 
gations of  Pringsheim,  Cramer,  Mettenius  and  others  on  other 
Pteridophytes. 
Considerable  light  was  thrown  on  the  nature  of  fertilization  in  the 
Algae  by  the  fortunate  discovery  by  Thuret  (1854)  of  the  process  as 
it  takes  place  in  Fucus.  This  was  followed  by  PringsheinVs  studies 
onVaucheria,  in  1855.  It  remained  for  De  Bary  to  study  the  fungi, 
and  he  proved  himself  to  be  one  of  the  greatest  masters  in  botanical 
science.  He  originated  methods  by  which  the  developmental  his- 
tory of  these  organisms  could  be  studied,  and  at  the  same  time 
showed  their  relation  to  their  hosts. 
