﻿442 
  R. 
  E. 
  TOMES 
  ON 
  LOWER-OOLITE 
  MADREPORARTA. 
  

  

  thicker. 
  They 
  have 
  synapticulae, 
  which 
  are 
  so 
  little 
  developed 
  that 
  

   they 
  have 
  the 
  appearance 
  of 
  little 
  points, 
  but 
  they 
  are 
  very 
  regular 
  

   as 
  to 
  size 
  and 
  distance 
  from 
  each 
  other. 
  

  

  The 
  rows 
  of 
  calices 
  ran 
  for 
  the 
  most 
  part 
  in 
  the 
  direction 
  of 
  the 
  

   greatest 
  length 
  of 
  the 
  calicular 
  surface. 
  The 
  greatest 
  number 
  I 
  

   have 
  seen 
  in 
  one 
  series 
  is 
  five. 
  They 
  are 
  deep, 
  and 
  have 
  a 
  small 
  

   but 
  deep 
  fossula, 
  which 
  is 
  without 
  a 
  trace 
  of 
  columella. 
  The 
  cycles 
  

   are 
  difficult 
  to 
  trace 
  ; 
  but 
  about 
  sixteen 
  septa 
  enter 
  into 
  the 
  forma- 
  

   tion 
  of 
  a 
  calice. 
  

  

  The 
  septa 
  and 
  septal 
  costoe 
  are 
  somewhat 
  equal 
  in 
  size 
  and 
  pro- 
  

   minence 
  ; 
  they 
  are 
  strongly 
  papillated 
  ; 
  and 
  the 
  latter, 
  as 
  is 
  usual 
  in 
  

   the 
  genus, 
  have 
  a 
  subcristiform 
  development 
  between 
  the 
  rows 
  of 
  

   calices. 
  They 
  never 
  anastomose. 
  They 
  are 
  much 
  less 
  regular 
  and 
  

   delicate 
  than 
  in 
  Oroseris 
  concentrica, 
  and 
  their 
  synapticulaB 
  are 
  

   very 
  smooth 
  and 
  irregular. 
  

  

  It 
  is 
  found 
  in 
  the 
  lower 
  reef 
  at 
  Crickley, 
  and 
  small 
  examples 
  are 
  

   common 
  ; 
  and 
  I 
  have 
  seen 
  one 
  from 
  the 
  same 
  horizon 
  at 
  Cooper's 
  

   Hill. 
  

  

  Oroseris 
  ixcrustans, 
  n. 
  sp. 
  (PI. 
  XVIII. 
  fig. 
  16.) 
  

  

  The 
  corallum 
  is 
  somewhat 
  foliaceous 
  and 
  incrusting 
  ; 
  and 
  the 
  

   upper 
  surface, 
  though 
  corresponding 
  with 
  the 
  surface 
  of 
  the 
  object 
  

   to 
  which 
  it 
  is 
  attached, 
  nevertheless 
  has 
  a 
  second 
  or 
  superimposed 
  

   part 
  of 
  much 
  smaller 
  size 
  than 
  the 
  one 
  which 
  it 
  lies 
  upon 
  ; 
  and 
  this 
  

   gives 
  to 
  the 
  corallum 
  a 
  slight 
  central 
  elevation. 
  The 
  outer 
  margin, 
  

   which 
  has 
  a 
  somewhat 
  rounded 
  or 
  subangular 
  form, 
  is 
  closely 
  ad- 
  

   pressed, 
  at 
  no 
  point 
  showing 
  the 
  least 
  disposition 
  towards 
  a 
  leaf- 
  

   like 
  or 
  upward 
  curl. 
  

  

  The 
  furrows 
  are 
  very 
  numerous, 
  short, 
  and 
  narrow, 
  and 
  the 
  

   ridges 
  between 
  them 
  of 
  corresponding 
  breadth. 
  Not 
  more 
  than 
  

   four 
  calices 
  appear 
  in 
  one 
  furrow 
  ; 
  and 
  they 
  are 
  more 
  frequently 
  

   two 
  or 
  three 
  together 
  ; 
  but 
  it 
  is 
  worthy 
  of 
  remark 
  that 
  on 
  no 
  part 
  

   of 
  the 
  corallum 
  are 
  they 
  scattered 
  singly 
  as 
  in 
  Thamnastrcea. 
  In 
  

   direction 
  the 
  furrows 
  follow 
  roughly 
  the 
  outline 
  of 
  the 
  corallum, 
  

   and 
  they 
  are 
  about 
  1| 
  line 
  apart. 
  

  

  The 
  calices 
  are 
  1| 
  line 
  apart; 
  they 
  are 
  not 
  deep 
  nor 
  very 
  clearly 
  

   defined. 
  The 
  septa 
  and 
  septal 
  costas 
  are 
  short, 
  rather 
  thick, 
  of 
  

   equal 
  size 
  and 
  prominence, 
  rather 
  closely 
  placed, 
  and 
  have 
  their 
  

   margins 
  furnished 
  with 
  closely 
  set 
  and 
  round 
  tubercles. 
  There 
  are 
  

   twelve 
  septa 
  in 
  each 
  calice. 
  

  

  The 
  greatest 
  diameter 
  of 
  the 
  corallum 
  is 
  3 
  inches. 
  

  

  One 
  specimen 
  only 
  has 
  been 
  obtained, 
  from 
  the 
  oolite 
  marl 
  

   (middle 
  reef) 
  at 
  Sheepscombe 
  by 
  Mr. 
  Wm. 
  Jenkins 
  of 
  Cheltenham. 
  

   It 
  is 
  attached 
  to 
  a 
  large 
  specimen 
  of 
  another 
  species 
  of 
  coral. 
  

  

  Oroseris 
  gibbosa, 
  n. 
  sp. 
  

  

  The 
  corallum 
  is 
  much 
  depressed 
  and 
  expanded, 
  its 
  under 
  surface 
  

   nearly 
  flat, 
  and 
  its 
  upper 
  surface 
  rising 
  into 
  rounded 
  or 
  elongated 
  

   prominences 
  or 
  gibbosities, 
  with 
  corresponding 
  deep 
  hollows. 
  

  

  

  