﻿82 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  Plate 
  X. 
  

  

  Fig. 
  1. 
  Ctenis 
  Leckenbyi 
  : 
  a, 
  portions 
  of 
  fronds, 
  three-fourths 
  the 
  natural 
  size 
  ; 
  

   b, 
  leaflet, 
  magnified 
  1£ 
  diameter. 
  

  

  2. 
  Otopteris 
  mediana 
  ; 
  portion 
  of 
  a 
  frond, 
  natural 
  size. 
  

  

  3. 
  Sphenopteris 
  modesta 
  : 
  a, 
  portions 
  of 
  two 
  fronds, 
  natural 
  size 
  ; 
  b, 
  leaflet, 
  

  

  magnified 
  4 
  diameters. 
  

  

  4. 
  Neuropteris 
  arguta 
  ; 
  portion 
  of 
  a 
  frond 
  in 
  fructification, 
  natural 
  size. 
  

  

  Plate 
  XI. 
  

  

  Fig. 
  1. 
  Pecopteris 
  polydaetyla 
  : 
  a, 
  frond 
  and 
  rachis, 
  natural 
  size 
  ; 
  b, 
  leaflet, 
  

   magnified 
  3 
  diameters. 
  

  

  2. 
  Tympanop 
  fiora 
  simplex 
  ; 
  portion 
  of 
  a 
  frond, 
  natural 
  size. 
  

  

  3. 
  Fucoides 
  erectus 
  : 
  a, 
  thallus, 
  natural 
  size 
  ; 
  b, 
  portion 
  of 
  a 
  thallus 
  in 
  

  

  fruit, 
  natural 
  size. 
  

  

  