﻿360 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  [Apr. 
  27, 
  

  

  the 
  surface 
  become 
  closed 
  and 
  empty 
  ; 
  they 
  consist 
  of 
  the 
  calicular 
  

   fossa 
  and 
  fossula, 
  the 
  interseptal 
  loculi, 
  the 
  more 
  or 
  less 
  cellular 
  

   spaces 
  between 
  the 
  septal 
  and 
  costal 
  dissejriments, 
  and 
  coencnchymal 
  

   tissue, 
  and, 
  in 
  porose 
  corals, 
  of 
  the 
  pores 
  and 
  reticulations. 
  

  

  I 
  now 
  propose 
  to 
  consider 
  and 
  to 
  describe 
  the 
  processes 
  which 
  

   in 
  modern 
  reefs 
  succeed, 
  as 
  they 
  doubtless 
  did 
  in 
  the 
  ancient, 
  the 
  

   displacement 
  and 
  death 
  of 
  masses 
  of 
  coral 
  ; 
  to 
  notice 
  how 
  these 
  pro- 
  

   cesses 
  may 
  possibly 
  have 
  influenced 
  the 
  mineralization 
  of 
  fossil 
  

   corals 
  ; 
  to 
  tabulate 
  the 
  forms 
  of 
  the 
  mineral 
  condition 
  of 
  the 
  West 
  

   Indian 
  Miocene 
  corals, 
  and 
  to 
  describe 
  those 
  forms 
  in 
  detail. 
  

  

  § 
  II. 
  Changes 
  in 
  recently 
  Dead 
  Corals. 
  

  

  In 
  the 
  coral-seas, 
  the 
  physical 
  causes 
  which 
  assist, 
  induce, 
  and 
  

   stimulate 
  chemical 
  affinity 
  are 
  strongly 
  and 
  constantly 
  in 
  operation. 
  

   The 
  solar 
  light 
  and 
  heat 
  are 
  intense, 
  and 
  the 
  temperature 
  of 
  the 
  sea 
  is 
  

   high 
  and 
  equable. 
  ■ 
  The 
  strong 
  swell 
  and 
  surf 
  are 
  highly 
  aerated, 
  

   and 
  teem 
  with 
  minute 
  organisms. 
  The 
  decomposition 
  of 
  the 
  dead 
  

   Zoophytes 
  and 
  Mollusca 
  is 
  therefore 
  very 
  rapid, 
  but 
  it 
  varies 
  con- 
  

   siderably 
  in 
  its 
  effects 
  upon 
  their 
  calcareous 
  parts, 
  according 
  to 
  the 
  

   position 
  of 
  the 
  coral 
  or 
  shell 
  during 
  the 
  post-mortem 
  changes. 
  

  

  Living 
  corals, 
  which 
  have 
  been 
  broken 
  off 
  the 
  parent 
  mass, 
  or 
  

   separated 
  from 
  their 
  basal 
  attachments, 
  are 
  liable 
  to 
  be 
  swept 
  up- 
  

   wards 
  and 
  carried 
  high 
  and 
  dry 
  by 
  the 
  force 
  of 
  the 
  waves. 
  In 
  

   many 
  instances 
  they 
  may 
  either 
  remain 
  in 
  their 
  original 
  position, 
  

   by 
  becoming 
  entangled 
  in 
  the 
  neighbouring 
  corals, 
  or 
  they 
  may 
  

   at 
  once 
  fall 
  to 
  the 
  bottom 
  of 
  the 
  sea 
  and 
  rest 
  on 
  the 
  surface 
  of 
  the 
  

   mud 
  which 
  forms 
  beneath 
  and 
  amidst 
  all 
  coral-reefs 
  and 
  banks. 
  

   Each 
  of 
  these 
  accidents 
  would 
  appear 
  to 
  be 
  followed 
  by 
  a 
  particular 
  

   series 
  of 
  physical 
  and 
  chemical 
  changes, 
  which 
  must 
  have 
  occurred 
  

   during 
  the 
  former 
  great 
  coral-eras 
  as 
  at 
  the 
  present 
  time, 
  and 
  which 
  

   appear 
  to 
  have 
  influenced 
  the 
  subsequent 
  mineralization 
  of 
  the 
  dead 
  

   sclerenchymal 
  structure 
  in 
  certain 
  definite 
  modes. 
  

  

  1. 
  By 
  the 
  action 
  of 
  the 
  sea. 
  — 
  Simple 
  corals, 
  or 
  compound 
  forms, 
  

   which 
  may 
  have 
  been 
  cast 
  up 
  high 
  and 
  dry 
  immediately 
  after 
  their 
  

   separation 
  from 
  a 
  reef 
  or 
  bank, 
  are 
  covered 
  with 
  soft 
  dermal 
  struc- 
  

   tures, 
  and 
  contain 
  the 
  digestive 
  and 
  ovarian 
  tissues. 
  Death 
  of 
  the 
  

   polypes 
  speedily 
  occurs, 
  and 
  either 
  their 
  soft 
  tissues 
  are 
  washed 
  out 
  of 
  

   the 
  sclerenchyma 
  during 
  the 
  process 
  of 
  rolling, 
  which 
  must 
  happen 
  

   during 
  the 
  recession 
  of 
  the 
  tide, 
  or 
  they 
  decompose 
  with 
  greater 
  

   or 
  less 
  rapidity 
  on 
  reaching 
  very 
  shallow 
  water 
  or 
  the 
  dry 
  shore. 
  

   It 
  would 
  appear 
  to 
  be 
  a 
  1 
  ale 
  that 
  the 
  minuter 
  structural 
  details 
  of 
  

   corals 
  are 
  best 
  preserved 
  when 
  the 
  animal 
  tissues 
  have 
  been 
  well 
  

   washed 
  out 
  by 
  the 
  sea, 
  and 
  that 
  the 
  loss 
  of 
  these 
  details 
  bears 
  a 
  

   relation 
  to 
  the 
  length 
  of 
  time 
  the 
  decomposing 
  soft 
  membranes 
  re- 
  

   main 
  in 
  contact 
  with 
  the 
  sclerenchyma. 
  The 
  indestructibility 
  of 
  

   corals, 
  whose 
  soft 
  parts 
  have 
  been 
  washed 
  out 
  before 
  decomposition 
  

   has 
  commenced, 
  is 
  well 
  known 
  ; 
  and 
  it 
  is 
  a 
  well-established 
  fact 
  that 
  

   the 
  sclerenchyma 
  of 
  such 
  corals 
  becomes 
  harder 
  by 
  exposure 
  : 
  the 
  

   perfection 
  of 
  their 
  details 
  is 
  of 
  course 
  limited 
  by 
  the 
  effects 
  of 
  roll- 
  

  

  