﻿MAItlNE 
  AND 
  ESTUARLTSTE 
  ALLUVIUM. 
  17 
  

  

  large 
  oyster 
  shells 
  which 
  all 
  lie 
  in 
  a 
  horizontal 
  position 
  and 
  between 
  the 
  

   laminae 
  composing 
  the 
  shell 
  the 
  black 
  clay 
  has 
  penetrated, 
  so 
  that 
  they 
  

   split 
  asunder 
  with 
  great 
  facility. 
  There 
  are 
  also 
  shells 
  of 
  the 
  cockle 
  

   and 
  other 
  kinds. 
  At 
  the 
  depth 
  of 
  27 
  feet 
  the 
  springs 
  of 
  water 
  began 
  to 
  

   gush; 
  the 
  stratum 
  becomes 
  softer 
  and 
  more 
  and 
  more 
  mixed 
  with 
  

   silicious 
  sand, 
  still 
  however 
  of 
  a 
  dark 
  slate 
  black 
  colour. 
  This 
  continues 
  

   to 
  37 
  feet, 
  the 
  lowest 
  point 
  to 
  which 
  the 
  well 
  was 
  dug, 
  when 
  lumps 
  

   of 
  what 
  I 
  suppose 
  to 
  be 
  green 
  martial 
  earth 
  were 
  found 
  intermixed 
  

   with 
  sand." 
  

  

  Close 
  to 
  the 
  Mylapur 
  tank 
  on 
  the 
  Mount 
  Eoad, 
  marine 
  shells 
  in 
  great 
  

  

  Shell-beds 
  exposed 
  near 
  W^tity, 
  and 
  all 
  of 
  exisl 
  ing 
  species, 
  were 
  obtained 
  

  

  the 
  Cenotaph. 
  m 
  s 
  i 
  n 
  k 
  m 
  g. 
  a 
  we 
  n 
  { 
  n 
  the 
  compound 
  of 
  Mr. 
  Ainslie's 
  

  

  house 
  a 
  little 
  north 
  of 
  the 
  Cenotaph. 
  Again, 
  in 
  the 
  Mowbray 
  Eoad, 
  

  

  about 
  half 
  a 
  mile 
  east 
  of 
  the 
  former 
  locality, 
  Sur- 
  

  

  In 
  Mylapur. 
  

  

  geon 
  Major 
  Porteous 
  found 
  numerous 
  marine 
  shells, 
  

   South 
  of 
  Madras 
  

   by 
  the 
  Coast 
  Canal 
  all 
  of 
  living 
  species, 
  in 
  a 
  sub-fossil 
  condition 
  imbed- 
  

  

  sections. 
  

  

  ded 
  in 
  black 
  sandy 
  clay. 
  How 
  far 
  west 
  of 
  the 
  

   Mylapur 
  tank 
  the 
  unequivocally 
  marine 
  beds 
  of 
  black 
  fossiliferous 
  clay 
  

   may 
  extend 
  in 
  this 
  great 
  bay 
  could 
  not 
  be 
  ascertained 
  owing 
  to 
  the 
  

   absence 
  of 
  sections 
  of 
  sufficient 
  depth. 
  In 
  a 
  well 
  sunk 
  not 
  far 
  from 
  

   Munro 
  bridge, 
  pale-yellow 
  sand 
  was 
  found 
  at 
  a 
  depth 
  of 
  30 
  feet 
  underly- 
  

   ing 
  the 
  bluish 
  black 
  or 
  black 
  stiff 
  clay. 
  

  

  In 
  a 
  large 
  well 
  sunk 
  about 
  a 
  quarter 
  of 
  a 
  mile 
  south 
  of 
  the 
  Pagoda 
  

   tank 
  in 
  Brodie's 
  Eoad, 
  the 
  same 
  black 
  clay 
  appeared 
  full 
  of 
  comminuted 
  

   fragments 
  of 
  shells. 
  The 
  canal 
  from 
  the 
  Adyar 
  to 
  the 
  Palar 
  south 
  of 
  

   Sadras 
  has 
  in 
  many 
  places 
  along 
  its 
  entire 
  length 
  been 
  dug 
  into 
  these 
  

   marine 
  beds 
  ; 
  the 
  black 
  or 
  grey 
  clay 
  thrown 
  up 
  on 
  the 
  sides 
  in 
  great 
  

   heaps 
  is 
  often 
  full 
  of 
  marine 
  shells. 
  These 
  fossil 
  shells 
  were 
  observed 
  in 
  

   greatest 
  quantity 
  along 
  the 
  south 
  coast 
  canal 
  from 
  its 
  opening 
  into 
  the 
  

   Adyar 
  to 
  the 
  bridge 
  south-east 
  of 
  Gruindy 
  Park. 
  A 
  little 
  to 
  the 
  south- 
  

   east 
  of 
  Onatoor 
  on 
  the 
  west 
  side 
  of 
  the 
  backwater 
  they 
  are 
  again 
  extremely 
  

   abundant. 
  The 
  shells 
  are 
  also 
  very 
  numerous 
  in 
  the 
  brine 
  pits 
  in 
  the 
  dry 
  

   c 
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  17 
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