﻿318 
  MR. 
  A. 
  C. 
  SEWARD 
  ON 
  THE 
  ASSOCIATION 
  OP 
  [Aug. 
  1 
  897, 
  

  

  of 
  rock 
  formed 
  largely 
  of 
  Glossopteris 
  leaf-beds, 
  it 
  would 
  seem 
  that 
  

   vast 
  tracts 
  of 
  country 
  must 
  have 
  been 
  covered 
  with 
  this 
  common 
  

   genus 
  of 
  ferns. 
  The 
  fact 
  of 
  this 
  very 
  great 
  abundance 
  of 
  the 
  leaves 
  

   of 
  a 
  plant 
  differing 
  but 
  little 
  in 
  shape 
  and 
  venation, 
  may 
  afford 
  some 
  

   confirmatory 
  evidence 
  in 
  favour 
  of 
  including 
  the 
  closely 
  similar 
  

   forms 
  of 
  leaves 
  in 
  one 
  species. 
  This 
  is 
  not, 
  indeed, 
  a 
  point 
  to 
  be 
  

   emphasized 
  ; 
  but 
  the 
  crowded 
  state 
  of 
  the 
  plants 
  over 
  wide 
  areas 
  is 
  

   not 
  entirely 
  favourable 
  to 
  the 
  association 
  of 
  closely-allied 
  species. 
  

  

  Glossopteris 
  Browniana, 
  Brongn. 
  

   ' 
  Prodr. 
  Hist. 
  Veg. 
  foss.' 
  p. 
  54 
  ; 
  ' 
  Hist. 
  Veg. 
  foss.' 
  p. 
  223 
  & 
  pi. 
  lxii. 
  

  

  Our 
  knowledge 
  of 
  this 
  species 
  has 
  recently 
  been 
  extended 
  by 
  the 
  

   exceedingly 
  interesting 
  facts 
  and 
  ingenious 
  interpretations 
  presented 
  

   by 
  M. 
  Zeiller 
  in 
  favour 
  of 
  the 
  opinion 
  that 
  Royle's 
  genus 
  Verte- 
  

   braria 
  is 
  the 
  rhizome 
  of 
  Glossopteris. 
  The 
  nature 
  of 
  Vertebraria, 
  

   first 
  described 
  by 
  Royle 
  in 
  1839, 
  1 
  has 
  long 
  been 
  a 
  puzzle 
  to 
  palaeo- 
  

   botanists. 
  Previous 
  to 
  Zeiller's 
  note 
  published 
  in 
  the 
  ' 
  Comptes 
  

   Rendus 
  ' 
  of 
  March 
  23rd, 
  1896, 
  and 
  the 
  more 
  complete 
  account 
  in 
  

   the 
  paper 
  previously 
  quoted, 
  the 
  nearest 
  approach 
  to 
  the 
  true 
  

   explanation 
  was 
  that 
  suggested 
  by 
  Bunbury 
  2 
  a 
  propos 
  of 
  an 
  

   unusually 
  good 
  specimen 
  which 
  he 
  described 
  from 
  Nagpur. 
  This 
  

   specimen, 
  now 
  in 
  the 
  Geological 
  Society's 
  Museum, 
  is 
  in 
  the 
  form 
  of 
  

   a 
  main 
  axis 
  of 
  the 
  Vertebraria-tyipe 
  giving 
  off 
  numerous 
  branched 
  

   roots. 
  Bunbury 
  expressed 
  the 
  opinion 
  that 
  Vertebraria 
  was 
  prob- 
  

   ably 
  the 
  root 
  of 
  a 
  plant, 
  possibly 
  Phyllotheca, 
  and 
  now 
  Zeiller 
  has 
  

   given 
  proof 
  of 
  its 
  rhizome 
  nature. 
  3 
  For 
  another 
  addition 
  to 
  our 
  

   knowledge 
  of 
  Glossopteris 
  we 
  are 
  also 
  mainly 
  indebted 
  to 
  M. 
  Zeiller. 
  

   Among 
  the 
  Glossopteris-fronds 
  from 
  ' 
  Francis,' 
  near 
  Johannesburg, 
  

   Zeiller 
  noticed 
  several 
  smaller 
  scale-like 
  leaves 
  having 
  the 
  same 
  

   anastomosing 
  venation 
  as 
  the 
  normal 
  and 
  larger 
  leaves, 
  but 
  without 
  

   a 
  midrib 
  ; 
  and 
  he 
  was 
  led 
  to 
  the 
  conclusion 
  that 
  Glossopteris 
  Brown- 
  

   iana 
  had 
  two 
  kinds 
  of 
  leaves. 
  He 
  compares 
  the 
  two 
  leaf-forms 
  

   borne 
  by 
  the 
  same 
  rhizome 
  with 
  the 
  large 
  fronds 
  and 
  small, 
  stiff, 
  

   scale-like 
  appendages 
  of 
  Onoclea 
  struthiopteris, 
  Hoffm. 
  Among 
  some 
  

   specimens 
  in 
  the 
  Bunbury 
  Collection 
  I 
  have 
  found 
  some 
  small 
  leaves 
  

   without 
  a 
  midrib, 
  exactly 
  similar 
  to 
  those 
  figured 
  by 
  Zeiller 
  in 
  

   association 
  with 
  the 
  typical 
  leaves 
  of 
  Glossopteris 
  Browniana 
  from 
  

   the 
  Newcastle 
  Beds 
  of 
  the 
  Hudson 
  Eiver, 
  New 
  South 
  Wales. 
  A 
  small 
  

   portion 
  of 
  this 
  specimen 
  is 
  shown 
  in 
  PI. 
  XXIII, 
  fig. 
  1 
  ; 
  at 
  s, 
  s\ 
  s" 
  

   are 
  seen 
  three 
  smaller 
  leaves 
  with 
  slightly 
  spreading 
  and 
  ana- 
  

   stomosing 
  veins. 
  The 
  most 
  perfect 
  of 
  these 
  leaves, 
  s, 
  has 
  a 
  length 
  

   of 
  1 
  cm. 
  and 
  a 
  breadth 
  of 
  6 
  mm. 
  ; 
  the 
  upper 
  surface 
  is 
  strongly 
  

  

  1 
  ' 
  Illustrations 
  of 
  the 
  Botany, 
  etc., 
  of 
  the 
  Himalayan 
  Mountains 
  & 
  of 
  the 
  

   Flora 
  of 
  Cashmere,' 
  vol. 
  i. 
  (1839) 
  p. 
  xxix.* 
  pi. 
  ii. 
  

  

  2 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xvii. 
  (1861) 
  p. 
  339. 
  

  

  3 
  [Since 
  this 
  paper 
  was 
  read 
  M. 
  Zeiller's 
  conclusions 
  have 
  been 
  confirmed 
  by 
  

   Mr. 
  E. 
  D. 
  Oldham, 
  who 
  has 
  published 
  figures 
  and 
  descriptions 
  of 
  Glossopteris- 
  

   fronds 
  attached 
  to 
  a 
  Vertebrarian 
  rhizome, 
  Eec. 
  Geol. 
  Surv. 
  India, 
  vol. 
  xxx. 
  

   pt. 
  i. 
  (1897) 
  p. 
  45.— 
  June 
  1st, 
  1897.] 
  

  

  