﻿260 
  G. 
  R. 
  Wieland 
  — 
  On 
  Liassic 
  Floras. 
  

  

  60* 
  Shales 
  ending 
  in 
  micaceous 
  sandstone 
  with 
  well-con- 
  

   served 
  cycads 
  above. 
  An 
  important 
  horizon, 
  and 
  the 
  

   highest 
  from 
  which 
  good 
  fossil 
  plants 
  were 
  secured.. 
  M. 
  6 
  # 
  5 
  

  

  61. 
  A 
  hard 
  conglomerate 
  ledge 
  with 
  a 
  dip 
  of 
  60°, 
  quartz- 
  

   itic 
  below 
  and 
  forming 
  a 
  waterfall. 
  Notable 
  feature 
  

  

  of 
  the 
  barranca. 
  (Cf. 
  upper 
  right 
  phot., 
  PI. 
  XL 
  VIII.) 
  M.12'5 
  

  

  62. 
  Soft 
  shaly 
  or 
  sandy 
  materials 
  ending 
  above 
  in 
  several 
  

   two-meter 
  thick 
  ledges 
  of 
  quartzitic 
  sandrock 
  M. 
  20 
  

  

  Note. 
  — 
  The 
  dip 
  here 
  sinks 
  from 
  60° 
  to 
  45° 
  with 
  a 
  

   slight 
  change 
  in 
  strike 
  from 
  nearly 
  N. 
  to 
  about 
  N. 
  

   10° 
  W. 
  

  

  63. 
  Shaly 
  ferruginous 
  layers 
  without 
  hard 
  ledges. 
  [Brachi- 
  

   opods 
  (undetermined) 
  in 
  Yuququimi 
  trail.].. 
  M. 
  23 
  

  

  64.* 
  Dark 
  and 
  compact 
  quartzite 
  containing 
  some 
  good 
  pin- 
  

   nules 
  of 
  cycads. 
  (Difficult 
  to 
  break 
  out 
  the 
  fossils, 
  and 
  

   no 
  collections 
  made 
  or 
  studied.) 
  Ml 
  

  

  65.* 
  Shales 
  often 
  bluish 
  in 
  tint, 
  nodular 
  and 
  ferruginous. 
  

  

  Plant 
  remains 
  very 
  indistinct 
  M. 
  16 
  -5 
  

  

  66. 
  Sandrock, 
  massive 
  below, 
  but 
  straticulate 
  above, 
  with 
  

   some 
  clayey 
  seams. 
  Forms 
  prominent 
  ledge 
  on 
  both 
  

   banks 
  of 
  barranca. 
  Contains 
  poorly 
  conserved 
  remains 
  

  

  of 
  large 
  stems 
  of 
  trees 
  - 
  . 
  M. 
  9 
  

  

  67. 
  Shales 
  somewhat 
  nodular 
  below, 
  but 
  not 
  above. 
  

   Easily 
  eroded, 
  and 
  because 
  followed 
  by 
  hard 
  shell 
  

   rocks 
  and 
  limestones 
  above, 
  responsible 
  for 
  sharp 
  turn 
  

   of 
  barranca 
  at 
  a 
  right 
  angle. 
  [The 
  course 
  of 
  the 
  

   barranca 
  follows 
  this 
  soft 
  horizon 
  for 
  about 
  200 
  meters 
  

   and 
  then 
  breaks 
  through 
  the 
  harder 
  rocks 
  above 
  along 
  

   the 
  course 
  of 
  a 
  small 
  fault 
  with 
  a 
  throw 
  of 
  about 
  a 
  

   meter 
  or 
  less.] 
  Marine 
  Liassic-Oolitic 
  superposition. 
  M. 
  5 
  

  

  Principal 
  Totals. 
  

  

  Meters. 
  

  

  1. 
  Entire 
  thickness 
  of 
  the 
  plant 
  beds 
  by 
  the 
  preliminary 
  

  

  measurements 
  with 
  allowances 
  for 
  lesser 
  faults, 
  M. 
  600, 
  

   the 
  corrected 
  total 
  being 
  5Q7 
  

  

  2. 
  Height 
  of 
  horizon 
  of 
  the 
  Williamsonia 
  Nathorstii 
  casts 
  

  

  above 
  eruptive 
  floor 
  85 
  

  

  3. 
  Height 
  from 
  eruptive 
  base 
  to 
  the 
  principal 
  coal 
  seam 
  

  

  horizon 
  with 
  JYoeggerathiopsis, 
  Otozamites 
  Mandelslohi 
  

   and 
  other 
  broad 
  short-leafed 
  Otozamitans 
  with 
  Ale- 
  

   thopterids, 
  etc. 
  . 
  _ 
  _ 
  - 
  . 
  100 
  

  

  4. 
  Base 
  of 
  plant 
  beds 
  up 
  to 
  Otozamites 
  hespera 
  zone 
  and 
  

   approximate 
  horizon 
  of 
  silicitied 
  Araucarioxylon 
  log... 
  240 
  

  

  5. 
  Approximate 
  thickness 
  of 
  lower 
  plant 
  beds 
  250 
  

  

  6. 
  Base 
  to 
  the 
  main 
  Williamsonia 
  horizon 
  350 
  

  

  The 
  interpretation 
  of 
  the 
  foregoing 
  measurements 
  is 
  in 
  the 
  

   light 
  of 
  the 
  plant 
  occurrences 
  entirely 
  simple. 
  It 
  is 
  obvious 
  

   that 
  coincident 
  with 
  land 
  emergence 
  there 
  was 
  a 
  more 
  or 
  less 
  

  

  