﻿432 
  Ortviann 
  — 
  Magellanian 
  Beds 
  of 
  Punta 
  Arenas. 
  

  

  previously*), 
  and 
  Mr. 
  Hatcher's 
  account 
  agrees 
  fairly 
  well 
  

   with 
  it, 
  with 
  the 
  only 
  exception 
  that 
  the 
  uppermost 
  fossilifer- 
  

   ous 
  bed 
  (horizon 
  Y) 
  has 
  not 
  been 
  noticed 
  by 
  Nordenskjold. 
  In 
  

   my 
  previous 
  report 
  I 
  have 
  shown 
  that 
  tin's 
  uppermost 
  horizon 
  

   agrees 
  palaeontologically 
  with 
  the 
  Suprapatagonian 
  beds, 
  true 
  

   Patagonian 
  beds 
  being 
  wanting 
  here. 
  This 
  question 
  has 
  been 
  

   settled 
  in 
  the 
  meantime 
  by 
  Mr. 
  Hatcher. 
  He 
  informs 
  me, 
  that 
  

   in 
  his 
  opinion, 
  there 
  is 
  no 
  difference 
  at 
  all 
  between 
  Patagonian 
  

   and 
  Suprapatagonian 
  deposits, 
  both- 
  being 
  only 
  different 
  yac^^6^ 
  

   of 
  one 
  and 
  the 
  same 
  series 
  of 
  deposits. 
  The 
  Suprapatagonian 
  

   facies 
  is 
  brought 
  about 
  by 
  a 
  prevailing 
  sandy 
  nature 
  of 
  the 
  de- 
  

   posit, 
  while 
  in 
  the 
  Patagonian 
  there 
  is 
  a 
  more 
  or 
  less 
  consider- 
  

   able 
  admixture 
  of 
  calcareous 
  matter. 
  It 
  is 
  true, 
  the 
  Supra- 
  

   patagonian 
  facies 
  is 
  chiefly 
  (but 
  not 
  always) 
  developed 
  near 
  the 
  

   top, 
  the 
  Patagonian 
  near 
  the 
  base 
  of 
  the 
  series, 
  but 
  between 
  

   base 
  and 
  top 
  these 
  facies 
  frequently 
  interlock, 
  giving 
  some- 
  

   times 
  the 
  appearance 
  of 
  a 
  discontinuity, 
  which 
  really 
  does 
  not 
  

   exist. 
  According 
  to 
  Mr. 
  Hatcher 
  there 
  is 
  no 
  discontinuity 
  

   between 
  Patagonian 
  and 
  Suprapatagonian 
  beds, 
  as 
  Ameghino 
  

   maintains; 
  in 
  fact, 
  he 
  found 
  it 
  absolutely 
  impossible 
  to 
  draw 
  a 
  

   line 
  between 
  these 
  two 
  deposits. 
  Mr. 
  Hatcher 
  reached 
  this 
  

   conclusion 
  by 
  an 
  examination 
  of 
  the 
  contact 
  of 
  both 
  deposits 
  

   near 
  Mt. 
  Observation, 
  and 
  at 
  numerous 
  other 
  places. 
  

  

  This 
  fact 
  confirms 
  the 
  opinion 
  of 
  the 
  w^riter 
  of 
  the 
  identity 
  

   of 
  both 
  deposits 
  formed 
  some 
  time 
  ago, 
  after 
  the 
  examination 
  

   of 
  the 
  palaeontological 
  material 
  at 
  hand, 
  and 
  the 
  comparison 
  of 
  

   it 
  with 
  V. 
  Ihering's 
  records 
  (after 
  Ameghino) 
  of 
  the 
  strati- 
  

   graphical 
  position 
  of 
  the 
  respective 
  fossils. 
  

  

  Further, 
  this 
  fact 
  explains 
  the 
  lack 
  of 
  Patagonian 
  beds 
  in 
  the 
  

   Punta 
  Arenas 
  section 
  : 
  if 
  Suprapatagonian 
  and 
  Patagonian 
  beds 
  

   are 
  only 
  different 
  facies 
  of 
  one 
  and 
  the 
  same 
  series 
  of 
  deposits, 
  

   they 
  are 
  practically 
  identical 
  ; 
  and 
  it 
  is 
  quite 
  clear 
  that 
  one 
  may 
  

   replace 
  the 
  other 
  completely 
  in 
  certain 
  localities; 
  and 
  this 
  is 
  

   exactly 
  what 
  we 
  observe 
  in 
  the 
  Punta 
  Arenas 
  section 
  : 
  the 
  

   Patagonian 
  beds 
  are 
  represented 
  there 
  not 
  by 
  the 
  Patagonian, 
  

   but 
  by 
  the 
  Suprapatagonian 
  ''facies." 
  

  

  PrincetoTi 
  University, 
  October 
  1 
  1 
  . 
  

  

  * 
  See 
  Xordeaskjold, 
  1. 
  c, 
  1898, 
  p. 
  24, 
  footnote. 
  A 
  section 
  of 
  this 
  locality 
  has 
  

   been 
  described 
  as 
  early 
  as 
  in 
  1873 
  by 
  Mallard 
  & 
  Fuchs 
  (Ann. 
  des 
  Mines, 
  ser. 
  7, 
  

   V. 
  3, 
  p. 
  97), 
  but 
  this 
  represents 
  only 
  deposits 
  above 
  the 
  coal. 
  Mallard 
  it 
  Fuchs 
  men- 
  

   tion 
  the 
  occurrence 
  of 
  a 
  largo 
  oyster 
  and 
  a 
  Pectuuculus 
  in 
  the 
  lower 
  part 
  of 
  their 
  

   section, 
  while 
  two 
  such 
  fossils 
  in 
  association 
  are 
  fouud 
  only 
  in 
  the 
  uppermost 
  

   horizon 
  (V)of 
  Mr, 
  Hatcher's 
  profile. 
  Thus 
  this 
  section 
  seems 
  to 
  begin 
  where 
  Mr. 
  

   Hatcher's 
  ends. 
  

  

  