﻿iv 
  KEY 
  AND 
  FLORA 
  

  

  may 
  be 
  found 
  worth 
  while, 
  in 
  the 
  case 
  of 
  some 
  /'/// 
  

   Buraglnacea', 
  and 
  Composite, 
  to 
  collect 
  fruit 
  during 
  the 
  sum- 
  

   mer 
  before 
  it 
  is 
  to 
  be 
  used, 
  preserve 
  it 
  either 
  dry 
  or 
  in 
  pre- 
  

   servative 
  fluid, 
  as 
  may 
  seem 
  best, 
  and 
  use 
  it 
  with 
  freshly 
  

   collected 
  flowers 
  in 
  the 
  determination 
  of 
  species. 
  

  

  No 
  systematic 
  work 
  with 
  seed 
  plants 
  can 
  be 
  of 
  much 
  use 
  

   unless 
  the 
  teacher 
  takes 
  constant 
  pains 
  to 
  bring 
  out 
  the 
  idea 
  

   of 
  actual 
  relationship 
  by 
  descent 
  among 
  the 
  forms 
  studied, 
  

   and 
  to 
  show, 
  in 
  the 
  simpler 
  cases 
  available, 
  some 
  of 
  the 
  steps 
  

   of 
  evolution. 
  The 
  beginner 
  must 
  not 
  be 
  allowed 
  to 
  suppose 
  

   that 
  the 
  flora 
  which 
  he 
  is 
  using 
  contains 
  more 
  than 
  a 
  small 
  

   fraction 
  of 
  the 
  total 
  number 
  of 
  plants 
  even 
  in 
  the 
  families 
  

   treated. 
  He 
  must 
  be 
  made 
  to 
  realize 
  that 
  the 
  Rubiacece, 
  for 
  

   instance, 
  of 
  which 
  he 
  has 
  fourteen 
  species 
  described, 
  really 
  

   number 
  as 
  many 
  as 
  4500 
  species, 
  and 
  the 
  Composites, 
  instead 
  

   of 
  mustering 
  a 
  few 
  dozen 
  strong, 
  number 
  in 
  all 
  at 
  least 
  12,000 
  

   species. 
  For 
  such 
  comparisons 
  Engler's 
  Syllabus 
  <l<-r 
  Pflanzen- 
  

   familien 
  will 
  be 
  found 
  to 
  contain 
  the 
  most 
  recent 
  and 
  compact 
  

   summary. 
  

  

  A 
  somewhat 
  complete 
  (phanerogamic) 
  flora 
  of 
  the 
  student's 
  

   region 
  should 
  be 
  constantly 
  in 
  use. 
  For 
  this 
  purpose 
  the 
  

   author 
  prefers 
  to 
  all 
  others 
  the 
  seventh 
  edition 
  of 
  Gray's 
  

   Ma 
  n 
  a 
  ul 
  of 
  Botany. 
  For 
  the 
  convenience 
  of 
  those 
  who 
  may 
  

   find 
  it 
  necessary 
  to 
  use 
  Britton's 
  M>nd 
  of 
  the 
  Flora 
  of 
  flu 
  1 
  

   Northern 
  States 
  and 
  Canada, 
  the 
  generic 
  name 
  used 
  by 
  Britton 
  

   will 
  generally 
  be 
  found 
  in 
  parenthesis 
  after 
  the 
  name 
  sanc- 
  

   tioned 
  by 
  the 
  Vienna 
  code. 
  In 
  cases 
  where 
  Britton's 
  genus 
  

   covers 
  only 
  part 
  of 
  the 
  genus 
  as 
  given 
  in 
  this 
  book, 
  a 
  state- 
  

   ment 
  to 
  that 
  effect 
  is 
  made, 
  as 
  on 
  p. 
  18f>, 
  --B. 
  Fl. 
  species 
  4 
  

   (Na/nn?>urr/ia). 
  For 
  suggestions 
  about 
  literature 
  see 
  Bergen 
  

   and 
  Davis, 
  Laboratory 
  and 
  Field 
  llmnml 
  of 
  Botany, 
  p. 
  230. 
  

  

  The 
  novice 
  should 
  find 
  a 
  good 
  deal 
  of 
  help 
  in 
  understand- 
  

   ing 
  the 
  structure 
  of 
  some 
  of 
  the 
  more 
  difficult 
  flowers 
  and 
  

   fruits 
  in 
  the 
  illustrations 
  which 
  accompany 
  several 
  families. 
  

   Most 
  of 
  these 
  have 
  been 
  redrawn 
  for 
  the 
  present 
  edition 
  by 
  

   Mr. 
  E. 
  N. 
  Fischer 
  of 
  Boston. 
  

  

  J. 
  Y. 
  B. 
  

  

  CAMBRIDGE, 
  MASSACHUSETTS 
  

  

  