﻿Related 
  Sedimentary 
  Surface 
  Forms. 
  253 
  

  

  alternating 
  dry 
  and 
  wet 
  seasons 
  for 
  the 
  region 
  lying 
  to 
  

   the 
  east 
  of 
  the 
  Bedford-Berea 
  sediments. 
  31 
  For 
  the 
  ter- 
  

   restrial 
  sediments 
  in 
  question, 
  the 
  comparison 
  with 
  the 
  

   monsoon 
  region 
  of 
  the 
  upper 
  Punjab 
  is 
  made, 
  which 
  

   seems 
  a 
  very 
  happy 
  one. 
  The 
  shallow 
  water 
  marine 
  sedi- 
  

   ments 
  of 
  our 
  Mississippian 
  seas 
  probably 
  find 
  their 
  

   closest 
  analogy 
  in 
  the 
  shelf 
  sea 
  north 
  of 
  Australia, 
  where 
  

   the 
  sea-bottom 
  is 
  largely 
  covered 
  by 
  ' 
  ' 
  a 
  very 
  fine-grained, 
  

   impalpable, 
  pale 
  olive-green 
  mud, 
  wholly 
  soluble 
  in 
  dilute 
  

   hydrochloric 
  acid, 
  and 
  therefore 
  essentially 
  carbonate 
  of 
  

   lime." 
  32 
  Along 
  the 
  Gulf 
  of 
  Carpentaria 
  the 
  dry 
  winds 
  

   from 
  the 
  deserts 
  to 
  the 
  south 
  must 
  carry 
  quantities 
  of 
  

   sand 
  into 
  the 
  sea 
  33 
  during 
  the 
  dry 
  season 
  from 
  April 
  to 
  

   November, 
  while 
  in 
  the 
  remaining 
  months 
  the 
  great 
  floods 
  

   produced 
  by 
  the 
  northwest 
  monsoon 
  34 
  must 
  furnish 
  con- 
  

   siderable 
  amounts 
  of 
  clastic 
  sediment. 
  

  

  Summary 
  : 
  — 
  It 
  is 
  in 
  a 
  relatively 
  small, 
  more 
  or 
  less 
  

   detached 
  portion 
  35 
  of 
  such 
  a 
  gulf 
  that 
  Bedford-Berea 
  sedi- 
  

   ments 
  were 
  laid 
  down. 
  The 
  parallelism 
  of 
  the 
  ripples 
  

   formed 
  in 
  it 
  may 
  be 
  due 
  to 
  a 
  peculiar 
  shape, 
  offering 
  the 
  

   wind 
  a 
  much 
  greater 
  fetch 
  in 
  one 
  direction 
  than 
  in 
  any 
  

   other. 
  In 
  that 
  case 
  the 
  greater 
  expanse 
  of 
  the 
  water 
  in 
  

   question 
  must 
  necessarily 
  have 
  been 
  to 
  the 
  southwest, 
  

   since 
  the 
  north 
  suffered 
  considerable 
  changes 
  during 
  the 
  

   time 
  of 
  the 
  formation 
  of 
  the 
  ripples. 
  

  

  In 
  view 
  of 
  the 
  distribution 
  especially 
  of 
  the 
  Berea 
  for- 
  

   mation 
  and 
  of 
  the 
  improbability 
  attached 
  to 
  the 
  assump- 
  

   tion 
  that 
  the 
  waterbody 
  kept 
  its 
  general 
  shape 
  while 
  

   perhaps 
  as 
  much 
  as 
  one-half 
  of 
  it 
  underwent 
  elevation, 
  

   erosion, 
  and 
  depression, 
  it 
  appears 
  highly 
  probable 
  that 
  

   winds 
  of 
  constant 
  direction 
  have 
  caused 
  this 
  remarkable 
  

   parallelism 
  of 
  ripples. 
  The 
  general 
  trend 
  of 
  these 
  rip- 
  

  

  31 
  See 
  preceding 
  footnote. 
  

  

  32 
  J. 
  D. 
  Dana, 
  Corals 
  and 
  Coral 
  Islands, 
  3d 
  edit., 
  p. 
  142, 
  1890. 
  

  

  33 
  Joh. 
  Walther, 
  Lithogenesis 
  der 
  Gegenwart, 
  1894, 
  p. 
  648. 
  

  

  34 
  J. 
  Hann, 
  Handbuch 
  der 
  Klimatologie, 
  vol. 
  2, 
  p. 
  288, 
  1910. 
  

  

  The 
  Arafura 
  Sea 
  with 
  the 
  Gulf 
  of 
  Carpentaria 
  and 
  the 
  South 
  China 
  Sea 
  

   with 
  the 
  Java 
  Sea 
  are 
  the 
  only 
  epicontinental 
  seas 
  of 
  the 
  present 
  geologic 
  

   period 
  offering 
  close 
  analogies 
  to 
  the 
  warm 
  shallow 
  seas 
  of 
  the 
  Paleozoic. 
  

   A 
  systematic 
  study 
  of 
  their 
  sediments 
  from 
  the 
  point 
  of 
  view 
  of 
  sedimentary 
  

   petrography 
  is 
  certainly 
  as 
  necessary 
  to 
  a 
  deeper 
  understanding 
  of 
  the 
  

   problems 
  involved 
  as 
  that 
  of 
  the 
  rocks 
  of 
  the 
  volcanic 
  islands 
  of 
  the 
  

   adjoining 
  deep 
  sea 
  is 
  to 
  igneous 
  petrography. 
  

  

  35 
  A 
  recent, 
  larger 
  example 
  of 
  such 
  a 
  detached 
  arm 
  of 
  an 
  epicontinental 
  

   sea 
  practically 
  without 
  tides 
  is 
  offered 
  by 
  the 
  Baltic 
  Sea, 
  which 
  during 
  the 
  

   Pleistocene, 
  for 
  a 
  time, 
  was 
  even 
  transformed 
  into 
  a 
  freshwater 
  lake. 
  

   (Comp. 
  E. 
  Kayser, 
  Lehrbuch 
  d. 
  Geol. 
  Formationskunde, 
  3d 
  edit., 
  p. 
  650, 
  

   1908.) 
  

  

  