﻿80 
  THEOBALD: 
  GEOLOGY 
  OF 
  PEGU. 
  

  

  VII. 
  — 
  Pegu 
  Group. 
  

   The 
  term 
  Pegu 
  group 
  is 
  proposed 
  for 
  a 
  very 
  important 
  series 
  of 
  

   beds, 
  intervening 
  between 
  the 
  Eocene 
  or 
  Nummulitic 
  group 
  on 
  the 
  one 
  

   hand 
  and 
  the 
  fossil-wood 
  group 
  on 
  the 
  other, 
  and 
  comprising 
  the 
  bulk 
  

   of 
  the 
  Pegu 
  range, 
  and 
  most 
  of 
  the 
  ground 
  intervening 
  between 
  the 
  

   Irrawadi 
  and 
  Sittoung 
  rivers, 
  together 
  with 
  a 
  considerable 
  tract 
  of 
  country- 
  

   West 
  of 
  the 
  Irrawadi 
  also. 
  Having 
  regard 
  to 
  its 
  superficial 
  extent, 
  it 
  is 
  

   the 
  most 
  important 
  group 
  in 
  the 
  Province 
  ; 
  it 
  is 
  far 
  richer 
  than 
  any 
  other 
  

   in 
  fossils, 
  and 
  is 
  better 
  defined 
  as 
  a 
  whole 
  as 
  regards 
  its 
  geological 
  age. 
  

   Although 
  many 
  -of 
  its 
  beds 
  are 
  rich 
  in 
  fossils 
  in 
  a 
  good 
  state 
  of 
  pre- 
  

   servation, 
  it 
  often 
  displays 
  a 
  great 
  thickness 
  of 
  beds 
  in 
  which 
  fossils 
  

   are 
  either 
  absent 
  or 
  ill-preserved. 
  From 
  what 
  we 
  know 
  of 
  the 
  

   fauna, 
  its 
  age 
  may 
  be 
  roughly 
  fixed 
  as 
  upper 
  Tertiary 
  ; 
  covering, 
  probably, 
  

   the 
  whole 
  of 
  the 
  geological 
  epochs 
  named 
  Miocene 
  and 
  Pliocene. 
  

   No 
  great 
  break 
  being 
  perceptible 
  after 
  the 
  close 
  of 
  the 
  Nummulitic 
  

   period, 
  to 
  which 
  group 
  its 
  lower 
  beds 
  would 
  seem 
  to 
  succeed 
  con- 
  

   formably, 
  and 
  an 
  unbroken 
  sequence 
  of 
  beds 
  continuing 
  up 
  to 
  the 
  

   fossil-wood 
  group 
  of 
  presumably 
  newer 
  Pliocene 
  age, 
  there 
  seems 
  good 
  

   grounds 
  for 
  believing 
  that 
  the 
  Pegu 
  group 
  covers 
  the 
  whole 
  of 
  the 
  above 
  

   named 
  period, 
  prodigious 
  as 
  it 
  . 
  is. 
  In 
  the 
  opinion 
  of 
  Dr. 
  Stoliczka, 
  no 
  

   effective 
  and 
  satisfactory 
  examination 
  of 
  the 
  fossils 
  of 
  this 
  series 
  can 
  be 
  

   undertaken 
  till 
  not 
  only 
  have 
  the 
  beds 
  containing 
  them 
  been 
  more 
  

   thoroughly 
  explored, 
  for 
  fossils 
  specially, 
  than 
  is 
  possible 
  during 
  the 
  

   exigencies 
  and 
  progress 
  of 
  a 
  first 
  survey, 
  but 
  till 
  a 
  complete 
  col- 
  

   lection 
  of 
  the 
  living 
  fauna 
  of 
  the 
  Bay 
  of 
  Bengal 
  is 
  available 
  for 
  compa- 
  

   rison, 
  which 
  does 
  not 
  at 
  present 
  exist. 
  It 
  is 
  clear 
  that 
  for 
  comparison 
  

   and 
  elucidation 
  of 
  a 
  Tertiary 
  fauna 
  a 
  collection 
  is 
  essential 
  of 
  the 
  organ- 
  

   isms 
  living 
  in 
  the 
  nearest 
  locality 
  where 
  faunal 
  conditions 
  still 
  exist 
  

   similar 
  to 
  those 
  prevailing 
  during 
  the 
  deposition 
  of 
  the 
  strata, 
  whose 
  

   fossils 
  are 
  being 
  investigated. 
  Great 
  as 
  is 
  the 
  thickness 
  and 
  extent 
  of 
  

   this 
  group, 
  it 
  offers 
  small 
  inducement 
  for 
  sub-division, 
  as 
  there 
  are 
  so 
  few 
  

   well 
  defined 
  beds 
  in 
  it, 
  capable 
  of 
  being 
  anywhere 
  recognised 
  and 
  taken 
  

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