﻿80 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  in 
  fructification, 
  the 
  fertile 
  and 
  infertile 
  leaflets 
  being 
  on 
  the 
  same 
  

   frond. 
  Specimens 
  entirely 
  in 
  the 
  former 
  condition 
  have 
  been 
  long 
  

   considered 
  a 
  distinct 
  species, 
  or 
  genus, 
  and 
  as 
  such 
  Mr. 
  Bean 
  informs 
  

   me 
  he 
  sent 
  examples 
  in 
  1838 
  to 
  M. 
  Adolphe 
  Brongniart, 
  who 
  re- 
  

   marked 
  on 
  them 
  as 
  follows 
  : 
  — 
  

  

  " 
  A 
  very 
  remarkable 
  Fern, 
  which 
  ought 
  to 
  constitute 
  a 
  new 
  genus 
  

   among 
  forest 
  ferns, 
  but 
  approaches 
  near 
  to 
  the 
  recent 
  ferns 
  of 
  the 
  

   tribe 
  Cyathea." 
  

  

  16. 
  Pecopteris 
  polydactyla, 
  Goepp. 
  PL 
  XI. 
  figs. 
  1 
  a, 
  lb. 
  

  

  Pecopteris 
  polydactyla, 
  Dunker, 
  Monogr. 
  

  

  Alethopteris 
  Goeppertii, 
  Ettingshausen. 
  Abhandlungen 
  der 
  k.-k. 
  

   geologischen 
  Beichsanstalt, 
  tab. 
  5. 
  figs. 
  1-7. 
  

  

  Yorkshire 
  examples 
  of 
  this 
  elegant 
  species 
  agree 
  so 
  well 
  with 
  the 
  

   figures 
  and 
  description 
  of 
  German 
  authors, 
  that 
  I 
  cannot, 
  notwith- 
  

   standing 
  (as 
  in 
  the 
  case 
  of 
  Sphenopteris 
  Jugleri) 
  their 
  occurrence 
  in 
  

   a 
  stratum 
  so 
  much 
  older, 
  refer 
  them 
  to 
  any 
  other 
  species. 
  The 
  ex- 
  

   ample 
  figured 
  (the 
  first 
  I 
  obtained) 
  is 
  finer 
  than 
  any 
  which 
  have 
  

   subsequently 
  occurred, 
  although 
  it 
  is 
  now 
  by 
  no 
  means 
  rare. 
  Its 
  mode 
  

   of 
  fructification 
  allies 
  it 
  with 
  Pohjpodites 
  rather 
  than 
  with 
  Pecopteris. 
  

  

  17. 
  Phlebopteris 
  propinqua, 
  Lindley 
  & 
  Hutton, 
  sp. 
  

  

  Pecopteris 
  propinqua, 
  Lindley 
  & 
  Hutton. 
  

   Pecopteris 
  crenifolia, 
  Phillips. 
  

   Phlebopteris 
  polypodioides, 
  Brongniart. 
  

   Phlebopteris 
  propinqua, 
  Brongniart. 
  

   Phlebopteris 
  contigua, 
  Lindley 
  & 
  Hutton. 
  

   Hemitilites 
  polypodioides, 
  Goeppert. 
  

  

  An 
  examination 
  of 
  the 
  original 
  specimen 
  of 
  Pecopteris 
  propinqua, 
  

   Lindley 
  & 
  Hutton 
  (Fossil 
  Flora, 
  p. 
  119), 
  now 
  in 
  the 
  Scarborough 
  

   Museum, 
  under 
  an 
  ordinary 
  pocket-lens, 
  at 
  once 
  shows 
  that 
  the 
  

   undulations 
  of 
  the 
  edges 
  of 
  the 
  leaflets, 
  relied 
  upon 
  as 
  a 
  specific 
  

   character, 
  are 
  merely 
  the 
  worn 
  jagged 
  edges 
  of 
  a 
  depauperated 
  Plant. 
  

   Precisely 
  the 
  same 
  appearance 
  is 
  given 
  to 
  the 
  figure 
  of 
  Pecopteris 
  

   crenifolia 
  in 
  Phillips's 
  ' 
  Geology 
  of 
  Yorkshire' 
  (pi. 
  8. 
  fig. 
  11), 
  and 
  

   from 
  the 
  same 
  cause, 
  as 
  an 
  examination 
  of 
  this 
  type 
  also 
  shows. 
  

   But 
  Lindley 
  and 
  Hutton 
  incorrectly 
  refer 
  it 
  to 
  their 
  Pecopteris 
  poly- 
  

   podioides, 
  the 
  venation 
  of 
  which 
  is 
  quite 
  distinct 
  from 
  that 
  of 
  the 
  

   species 
  under 
  consideration, 
  there 
  being 
  in 
  P. 
  polypodioides 
  no 
  distinct 
  

   areola, 
  and 
  the 
  sori 
  being 
  placed 
  at 
  the 
  tip 
  of 
  a 
  short 
  nerve, 
  as 
  

   is 
  shown 
  with 
  tolerable 
  accuracy 
  in 
  their 
  figure 
  of 
  the 
  magnified 
  

   portion 
  (pi. 
  60. 
  fig. 
  2). 
  Much 
  confusion 
  has 
  been 
  created 
  by 
  Lind- 
  

   ley 
  and 
  Hutton 
  having 
  adopted 
  the 
  specific 
  name 
  " 
  polypodioides 
  " 
  

   of 
  Brongniart's 
  'Prodrome' 
  for 
  a 
  species 
  which 
  his 
  'Histoire' 
  proved 
  

   to 
  be 
  quite 
  different 
  from 
  their 
  species, 
  and 
  which 
  the 
  evidence 
  of 
  

   many 
  specimens 
  proves 
  to 
  have 
  been 
  the 
  same 
  as 
  their 
  Phlebopteris 
  

   contigua, 
  as 
  they 
  rightly 
  conjecture. 
  Notwithstanding 
  the 
  differ- 
  

   ences 
  to 
  which 
  they 
  refer, 
  Phlebopteris 
  contigua 
  again 
  is 
  only 
  the 
  

   robust 
  condition 
  of 
  Pecopteris 
  propinqua 
  or 
  P. 
  crenifolia. 
  

  

  