﻿iSpo.J 
  

  

  BOTANICAL 
  GAZETTE. 
  177 
  

  

  Theroots 
  of 
  Marsilia 
  were 
  hardened 
  with 
  chromic 
  acid 
  

   and 
  stained 
  on 
  the 
  slide 
  with 
  gentian 
  violet. 
  The 
  methods 
  

   emploj-ed 
  with 
  Equisetum 
  gave 
  good 
  results 
  in 
  this 
  case 
  

   also. 
  The 
  sections 
  were 
  made 
  with 
  a 
  Minot 
  microtome 
  and 
  

   ran 
  1800 
  to 
  the 
  inch. 
  

  

  r;„ 
  ^Y^A^ATiox 
  OP 
  Figures 
  1 
  and 
  2.-Drawn 
  with 
  a 
  Zeiss 
  camera. 
  

   ^ 
  .1 
  V 
  ^°°gi,^»9"»I 
  section 
  of 
  root-tip 
  of 
  Marsilia 
  quadrifolia 
  X300. 
  Pig. 
  

   arptr? 
  n 
  ^-^l^^setum 
  arvense 
  X187. 
  In 
  both 
  figures 
  the 
  reference 
  letters 
  

   P 
  rl; 
  k 
  '^ 
  • 
  ?' 
  ^P^^^^ 
  ^®^' 
  ' 
  "' 
  I"' 
  V' 
  VI, 
  etc., 
  segments 
  of 
  body 
  of 
  root 
  ; 
  

   5ll 
  f 
  1 
  ' 
  P' 
  ^""^^*^ 
  ^^^^^ 
  ^^ 
  periblem 
  ;P 
  C, 
  plerome 
  cylinder 
  ; 
  p 
  c, 
  initial 
  

   T,l, 
  pleroiTie 
  cyhnder 
  ; 
  E, 
  deriuatogen 
  ; 
  h, 
  hypodermal 
  layer 
  ; 
  r', 
  r", 
  r*", 
  

   * 
  ' 
  r 
  , 
  successive 
  segments 
  of 
  root-cap 
  ; 
  d, 
  endodermis. 
  

  

  Botanical 
  Laboratory, 
  University 
  0/ 
  Indiana. 
  

  

  BEIEFEE 
  AETICLES. 
  

  

  Origin 
  of 
  the 
  houey-secretin^ 
  organs;— 
  A 
  few 
  sentences 
  from 
  Stad- 
  

   era 
  work 
  " 
  Zur 
  Kenntniss 
  der 
  Nectarien 
  "' 
  seem 
  to 
  me 
  to 
  throw 
  some 
  

   igbt 
  on 
  the 
  probable 
  origin 
  of 
  the 
  honey-secreting 
  organs 
  of 
  flowers. 
  

  

  He 
  says 
  (I 
  give 
  free 
  translations): 
  "The 
  vessels 
  which 
  are 
  always 
  

   present, 
  if 
  not 
  in 
  the 
  tissue 
  of 
  the 
  nectary 
  itself, 
  then 
  in 
  its 
  substratum, 
  

   glT 
  ^^"^"^' 
  ^^^^^ 
  strongly 
  developed, 
  terminating 
  in 
  the 
  border 
  of 
  the 
  

  

  8 
  and 
  tissue; 
  indeed 
  their 
  more 
  delicate 
  elements, 
  the 
  cambiform, 
  pene- 
  

   trate 
  it. 
  '■■'' 
  

  

  jj 
  ^^' 
  "The 
  nectaries 
  not 
  only 
  satisfy 
  the 
  demand 
  of 
  insects 
  for 
  

   ney, 
  but 
  also 
  account 
  for 
  the 
  loss 
  of 
  water 
  through 
  evaporation, 
  which 
  

   '» 
  always 
  considerable."* 
  

  

  excp 
  V^^ 
  ^^^'^ 
  ■ 
  " 
  ■'■^ 
  *^^ 
  vicinity 
  of 
  the 
  nectary 
  I 
  found 
  almost 
  without 
  

   cau^^ 
  f 
  ^ 
  ^*^"^^ 
  chlorophyll-bearing 
  tissue. 
  Even 
  in 
  regions 
  where, 
  be- 
  

   und 
  '^,, 
  '^^^^^^'^ 
  conditions, 
  one 
  would 
  not 
  expect 
  it; 
  as 
  in 
  Lilium 
  auratum 
  

   the 
  ^ 
  '^^ctary 
  between 
  the 
  two 
  vascular 
  strands; 
  in 
  the 
  hood 
  and 
  in 
  

   niay 
  b 
  • 
  h 
  ^^^^"^° 
  of 
  Asclepias 
  Cornuti, 
  etc. 
  These 
  chlorophyll 
  tissues 
  

   •^boraf 
  . 
  "^^^^^^^ 
  alone, 
  or 
  together 
  with 
  others 
  further 
  away, 
  be 
  the 
  

   rigg 
  ^ 
  ^^^^^ 
  ^^^ 
  the 
  manufacture 
  of 
  the 
  carbo-hydrates 
  which 
  the 
  necta- 
  

   ina 
  f 
  ' 
  ^ 
  i^ay, 
  under 
  no 
  circumstances, 
  give 
  them 
  to 
  the 
  nectary 
  

  

  ThTfi 
  ^'^^'^^^^ 
  capable 
  of 
  secretion." 
  

   stamen^ 
  ^f*^ 
  °^ 
  !^^^^® 
  statements 
  is 
  not 
  surprising. 
  In 
  order 
  to 
  supply 
  

   ^^Q 
  gra^ 
  ovaries 
  with 
  the 
  food 
  materials 
  so 
  abundantly 
  stored 
  in 
  pol- 
  

   --— 
  ^lff^;^_ovules, 
  there 
  should 
  be 
  a 
  strong 
  current 
  of 
  water 
  continu- 
  

  

  ^•■"i, 
  188?^® 
  ^""^ 
  Kenntniss 
  der 
  Nectarien 
  und 
  Biologic 
  derBliithen" 
  von 
  Dr. 
  Stadler. 
  

   ' 
  P. 
  70. 
  

  

  T 
  

  

  