﻿K. 
  P. 
  TOJTES 
  OK 
  LOWER-OOLTTE 
  MADREPORARIA. 
  443 
  

  

  There 
  is 
  no 
  epitheca; 
  but 
  the 
  whole 
  of 
  the 
  under 
  part 
  has 
  

   flexuous 
  and 
  indistinct 
  mural 
  costae. 
  

  

  No 
  particular 
  direction 
  is 
  observed 
  by 
  the 
  lines 
  of 
  calices 
  in 
  this 
  

   species. 
  The 
  longest 
  furrows 
  contain 
  about 
  seven 
  or 
  eight 
  calices. 
  

   They 
  are 
  shallow 
  ; 
  but 
  the 
  ridges 
  between 
  them, 
  though 
  without 
  

   much 
  prominence, 
  are 
  much 
  more 
  angular 
  than 
  in 
  the 
  other 
  species 
  

   here 
  described. 
  They 
  have 
  a 
  breadth 
  of 
  about 
  two 
  lines. 
  

  

  The 
  calices 
  are 
  near 
  together 
  in 
  the 
  furrows, 
  only 
  one 
  line 
  apart, 
  

   and 
  are 
  superficial. 
  About 
  twelve 
  septa 
  constitute 
  the 
  calice. 
  The 
  

   septa 
  and 
  septal 
  costae 
  are 
  thick, 
  irregular, 
  flexuous, 
  sometimes 
  

   quite 
  crooked, 
  often 
  anastomosing, 
  and 
  not 
  very 
  closely 
  placed. 
  

   Their 
  margins 
  appear 
  to 
  have 
  had 
  irregular 
  and 
  rugged 
  tubercles, 
  

   which 
  have 
  been 
  for 
  the 
  most 
  part 
  rubbed 
  off. 
  

  

  A 
  single 
  specimen 
  has 
  been 
  taken 
  from 
  the 
  lower 
  Trigonia-grit 
  

   at 
  Leckhampton 
  Hill, 
  by 
  Mr. 
  Wm. 
  Jenkins 
  of 
  Cheltenham. 
  

  

  The 
  foregoing 
  five 
  species 
  of 
  Oroseris 
  may 
  be 
  easily 
  distinguished 
  

   from 
  each 
  other 
  by 
  the 
  following 
  very 
  brief 
  descriptions 
  : 
  — 
  

  

  0. 
  oolitica 
  by 
  its 
  size 
  and 
  very 
  deeply 
  wrinkled 
  epitheca, 
  and 
  by 
  

   the 
  very 
  unequal 
  degree 
  of 
  prominence 
  of 
  the 
  septa. 
  

  

  0. 
  concentrica 
  by 
  its 
  turbinate 
  form, 
  rudimentary 
  epitheca, 
  

   regular 
  and 
  delicate 
  septal 
  costae, 
  and 
  concentric 
  arrangement 
  of 
  

   the 
  lines 
  of 
  calices. 
  

  

  0. 
  incrustans 
  by 
  its 
  incrusting 
  habit, 
  short 
  lines 
  of 
  calices, 
  and 
  

   relatively 
  stout 
  but 
  regular 
  and 
  closely 
  placed 
  septal 
  costae. 
  

  

  0. 
  gibbosa 
  by 
  the 
  irregular 
  form 
  of 
  the 
  corallum, 
  absence 
  of 
  

   epitheca, 
  and 
  by 
  its 
  crooked, 
  irregular, 
  and 
  stout 
  septal 
  costae. 
  

  

  0. 
  contorta 
  by 
  its 
  distorted 
  form, 
  and 
  by 
  having 
  the 
  calices 
  in 
  

   rows 
  rudely 
  corresponding 
  with 
  the 
  outer 
  boundary 
  of 
  the 
  calicular 
  

   surface. 
  It 
  most 
  nearly 
  resembles 
  0. 
  concentrica, 
  but 
  has 
  fewer 
  

   calices, 
  and 
  longer 
  as 
  well 
  as 
  stouter 
  septal 
  costae. 
  

  

  Genus 
  Microsolena, 
  Lamx. 
  

  

  Since 
  the 
  establishment 
  of 
  this 
  genus 
  by 
  Lamouroux, 
  in 
  1821, 
  it 
  

   has 
  received 
  at 
  the 
  hands 
  of 
  MM. 
  Edwards 
  and 
  Haime 
  such 
  revi- 
  

   sion 
  as 
  was 
  necessary 
  to 
  fit 
  it 
  for 
  the 
  reception 
  of 
  the 
  group 
  of 
  

   perforate 
  corals 
  placed 
  in 
  it 
  by 
  them, 
  the 
  original 
  describer 
  not 
  

   having 
  fully 
  understood 
  its 
  true 
  structure 
  and 
  affinities. 
  

  

  Michelin, 
  in 
  his 
  work 
  on 
  the 
  fossil 
  corals 
  of 
  France, 
  while 
  ad- 
  

   mitting 
  the 
  species 
  on 
  which 
  Lamouroux 
  had 
  founded 
  the 
  genus, 
  did 
  

   not 
  adopt 
  the 
  genus, 
  but 
  placed 
  the 
  type 
  species 
  in 
  the 
  genus 
  

   Alveopora 
  ; 
  and 
  M'Coy, 
  following 
  Michelin, 
  so 
  far 
  as 
  the 
  species 
  is 
  

   concerned, 
  made 
  use 
  of 
  the 
  genus 
  Siderastrcea. 
  

  

  More 
  recently 
  Milaschewitsch 
  has 
  added 
  much 
  to 
  our 
  knowledge 
  

   of 
  the 
  species 
  of 
  Microsolena, 
  by 
  pointing 
  out 
  the 
  near 
  relationship 
  

   of 
  the 
  genus 
  to 
  Thamnastrcea 
  ; 
  and 
  removing 
  the 
  latter 
  wholly 
  from 
  

   the 
  Pungidae, 
  he 
  has 
  placed 
  it 
  among 
  the 
  Poritidae 
  and 
  in 
  close 
  

   proximity 
  to 
  Microsolena. 
  

  

  2h2 
  

  

  