﻿426 
  R. 
  P. 
  TOMES 
  ON 
  LOWER-OOLITE 
  MADREPORARIA. 
  

  

  the 
  synonymy 
  as 
  above 
  ; 
  but 
  there 
  are 
  other 
  respects 
  in 
  which 
  the 
  

   present 
  species 
  differs 
  from 
  the 
  species 
  of 
  Oonfusastrcea 
  which 
  is 
  now 
  

   also 
  named 
  tenuistriata. 
  The 
  septa 
  are 
  much 
  more 
  closely 
  placed 
  ; 
  and 
  

   occasionally 
  those 
  of 
  the 
  newer 
  run 
  into 
  the 
  older 
  ones. 
  Besides 
  

   this, 
  there 
  is 
  a 
  common 
  basal 
  wall, 
  of 
  an 
  expanded 
  turbinate 
  form, 
  

   which 
  has 
  the 
  costae 
  considerably 
  exposed, 
  and 
  is 
  encircled 
  by 
  

   narrow 
  rings 
  of 
  epitheca 
  ; 
  gemmation 
  is 
  pretty 
  frequent, 
  and 
  takes 
  

   place 
  from 
  the 
  walls, 
  in 
  the 
  angles 
  where 
  they 
  meet 
  those 
  of 
  other 
  

   calices. 
  

  

  The 
  most 
  typical 
  examples 
  have 
  been 
  procured 
  from 
  the 
  Trigonia- 
  

   grit 
  at 
  Ravensgate 
  Hill 
  and 
  Birdlip 
  Hill 
  : 
  and, 
  so 
  far 
  as 
  I 
  am 
  

   aware, 
  it 
  does 
  not 
  occur 
  in 
  either 
  of 
  the 
  other 
  zones 
  of 
  the 
  Glou- 
  

   cestershire 
  Oolite. 
  

  

  IsASTRiEA 
  DEPRESSA, 
  Tomes. 
  

  

  Isastrrpa 
  expansa, 
  Tomes, 
  Geol. 
  Mag. 
  vol. 
  v. 
  1878. 
  

  

  Since 
  the 
  appearance 
  of 
  my 
  former 
  paper, 
  I 
  have 
  learned 
  that 
  the 
  

   name 
  I 
  had 
  given 
  to 
  this 
  species 
  was 
  already 
  made 
  use 
  of 
  ; 
  and 
  I 
  

   now 
  therefore 
  substitute 
  the 
  above. 
  

  

  This 
  is 
  a 
  common 
  species 
  in 
  the 
  lower 
  reefs 
  at 
  Cricldey 
  and 
  the 
  

   Horse 
  Pools 
  ; 
  but, 
  owing 
  to 
  its 
  thinness, 
  it 
  is 
  seldom 
  met 
  with 
  except 
  

   in 
  fragments. 
  It 
  is 
  desirable 
  to 
  state 
  that 
  subsequent 
  research 
  has 
  

   led 
  me 
  to 
  suspect 
  that 
  this 
  species 
  is 
  by 
  no 
  means 
  typical 
  of 
  the 
  

   genus 
  Tsastrcea. 
  The 
  continuity 
  of 
  the 
  septa 
  over 
  the 
  thick 
  walls, 
  

   as 
  in 
  the 
  Isastrcea 
  foliacea 
  of 
  M. 
  de 
  Fronientel, 
  from 
  the 
  Portland 
  

   Oolite 
  of 
  France, 
  is 
  very 
  suggestive 
  of 
  septal 
  costae 
  and 
  anexotheca, 
  

   the 
  existence 
  of 
  which 
  would 
  remove 
  this 
  species 
  from 
  the 
  present 
  

   genus. 
  At 
  present, 
  however, 
  I 
  have 
  failed 
  to 
  discover 
  either 
  exo- 
  

   theca, 
  dissepiments, 
  or 
  synapticula3. 
  

  

  Genus 
  Latimjsandra, 
  d'Orb. 
  

  

  Latimjeandra 
  Flemtngi, 
  Edw. 
  and 
  Haime, 
  Brit. 
  Foss. 
  Cor. 
  pt. 
  ii. 
  p. 
  

  

  136, 
  pi. 
  xxvii. 
  fig. 
  9. 
  

  

  This 
  is 
  a 
  common 
  species 
  at 
  Crickley 
  Hill, 
  but 
  it 
  is 
  almost 
  always 
  

   crystalline 
  inside, 
  and 
  sometimes 
  is 
  nothing 
  more 
  than 
  a 
  hollow 
  cast. 
  

   This 
  I 
  have 
  repeatedly 
  observed, 
  whilst 
  Tharnnastrcece 
  taken 
  almost 
  

   in 
  contact 
  with 
  it 
  usually 
  have 
  the 
  internal 
  parts 
  well 
  preserved. 
  

  

  Latlm^andra 
  Davidsoni, 
  Edw. 
  and 
  Haime, 
  Brit. 
  Foss. 
  Cor. 
  pt. 
  ii. 
  p. 
  

  

  137, 
  pi. 
  xxxvii. 
  fig. 
  10. 
  

  

  Occurs 
  in 
  the 
  lower 
  reef 
  at 
  Crickley 
  Hill. 
  

  

  Latim^axdra 
  Haimei, 
  n. 
  sp. 
  (PI. 
  XVIII. 
  fig. 
  15.) 
  

  

  The 
  corallum 
  has 
  an 
  irregular 
  expanded 
  form, 
  and 
  is 
  wider 
  than 
  

   high. 
  The 
  under 
  surface 
  exhibits 
  a 
  broad 
  peduncle, 
  overhung 
  by 
  

   the 
  upper 
  part, 
  which 
  is 
  somewhat 
  fungiform 
  with 
  a 
  convex 
  upper 
  

   surface. 
  

  

  The 
  under 
  part 
  is 
  rugged 
  and 
  wholly 
  without 
  epitheca 
  ; 
  the 
  mural 
  

  

  