﻿NEGRAIS 
  ROCKS. 
  Ill 
  

  

  has 
  since 
  then 
  been 
  obtained; 
  and 
  I 
  shall 
  therefore 
  retain 
  the 
  term 
  with 
  

   a 
  somewhat 
  extended 
  application, 
  making 
  it 
  embrace 
  all 
  the 
  rocks 
  met 
  

   with 
  in 
  the 
  above 
  district 
  older 
  than 
  the 
  Nummulitic, 
  and 
  newer 
  than 
  

   the 
  Triassic. 
  It 
  is 
  by 
  no 
  means 
  certain 
  that 
  some 
  of 
  the 
  rocks 
  

   which 
  I 
  have 
  included 
  in 
  this 
  group 
  may 
  not 
  really 
  be, 
  as 
  I 
  at 
  first 
  

   surmised, 
  of 
  Eocene 
  age 
  ; 
  but 
  as 
  there 
  is 
  no 
  adequate 
  proof 
  of 
  this, 
  it 
  is 
  

   fruitless 
  attempting 
  to 
  solve 
  the 
  age 
  of 
  any 
  members 
  of 
  this 
  group. 
  

   From 
  the 
  general 
  absence 
  of 
  fossils 
  in 
  the 
  lower 
  portion 
  of 
  the 
  Nummu- 
  

   litic 
  group 
  and 
  a 
  similar 
  deficiency 
  in 
  the 
  beds 
  I 
  am 
  now 
  referring 
  to, 
  

   any 
  attempt 
  to 
  demarcate 
  the 
  limits 
  of 
  either 
  group 
  must 
  more 
  or 
  less 
  

   •rest 
  on 
  empirical 
  and 
  general 
  reasons, 
  than 
  on 
  valid 
  and 
  particular 
  ones 
  ; 
  

   and 
  the 
  same 
  difficulty 
  is 
  no 
  less 
  felt, 
  as 
  regards 
  the 
  relation 
  of 
  the 
  present 
  

   group 
  to 
  the 
  older 
  one 
  in 
  contact 
  with 
  it, 
  than 
  as 
  regards 
  that 
  which 
  

   immediately 
  succeeds 
  it. 
  In 
  the 
  Northern 
  part 
  of 
  the 
  Sandoway 
  district, 
  

   beds 
  of 
  Cretaceous 
  age 
  (Cenomanien) 
  come 
  in 
  and 
  extend 
  down 
  as 
  low 
  as 
  

   the 
  parallel 
  of 
  Kyeantulee. 
  It 
  is 
  therefore 
  highly 
  probable 
  that 
  these 
  

   beds 
  are 
  continued 
  down, 
  along 
  the 
  coast, 
  and 
  included 
  in 
  the 
  Negrais 
  

   rocks 
  ; 
  though 
  from 
  causes 
  already 
  specified, 
  it 
  is 
  not 
  easy 
  to 
  determine 
  

   whether 
  these 
  consist 
  mainly 
  of 
  beds 
  properly 
  referable 
  to 
  the 
  Eocene 
  or 
  

   to 
  the 
  Cretaceous. 
  

  

  My 
  original 
  restriction 
  of 
  the 
  band 
  within 
  narrower 
  limits 
  than 
  I 
  

   now 
  adopt, 
  was 
  based 
  on 
  the 
  belief 
  of 
  its 
  unconformity 
  to 
  a 
  series 
  of 
  beds 
  

   which 
  1 
  now 
  include 
  in 
  it 
  — 
  an 
  opinion 
  founded 
  mainly 
  on 
  a 
  section 
  seen 
  

   between 
  tidemarks 
  at 
  Satwah, 
  which 
  I 
  then 
  supposed 
  to 
  indicate 
  uncon- 
  

   formity, 
  but 
  which 
  I 
  now 
  consider 
  capable 
  of 
  being 
  otherwise 
  explained. 
  

   At 
  Satwah 
  a 
  great 
  expanse 
  of 
  pale 
  and 
  dark 
  gray 
  shales, 
  with 
  traces 
  of 
  car- 
  

   bonaceous 
  matter, 
  and 
  occasional 
  nodular 
  concretions 
  of 
  limestone, 
  occurs, 
  

   planed 
  down 
  between 
  tidemarks, 
  and 
  forming 
  rocky 
  patches 
  and 
  reefs 
  off 
  the 
  

   coast 
  here. 
  These 
  beds 
  have 
  a 
  general 
  South-east 
  dip, 
  and 
  some 
  of 
  them 
  are 
  

   suggestive 
  of 
  ash-beds, 
  though 
  they 
  contain 
  no 
  extraneous 
  fragments. 
  

   On 
  the 
  exposed 
  edges 
  of 
  these 
  shales, 
  blocks 
  of 
  a 
  very 
  different 
  mineral 
  

  

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