﻿G. 
  It. 
  Wieland 
  — 
  On 
  Liassic 
  Floras. 
  257 
  

  

  Preliminary 
  Record 
  and 
  Measurement 
  of 
  the 
  Seccion 
  

  

  Consuelo. 
  

  

  A. 
  The 
  Plant 
  Becls.\ 
  

   (Fossil 
  Plant 
  "bearing 
  strata 
  are 
  indicated 
  by 
  a 
  *.) 
  

  

  0. 
  Eruptive 
  floor 
  and 
  intrusives. 
  Ends 
  at 
  and 
  produces 
  

   two 
  small 
  gullies 
  running 
  directly 
  up 
  from 
  both 
  sides 
  

   of 
  barranca. 
  Dip 
  of 
  floor 
  is 
  30°, 
  which 
  is 
  similar 
  to 
  

   that 
  of 
  the 
  overlying 
  sedimentaries. 
  

  

  1. 
  First 
  member 
  of 
  the 
  sedimentaries. 
  Forms 
  the 
  

   west 
  slope 
  of 
  the 
  above 
  gullies 
  as 
  result 
  of 
  erosion. 
  

   Clayey 
  shaly 
  bed 
  too 
  soft 
  to 
  form 
  sharp 
  ledges. 
  Cov- 
  

   ered 
  by 
  grassy 
  growth 
  in 
  distinct 
  contrast 
  to 
  the 
  erup- 
  

   tive 
  floor, 
  which 
  is 
  usually 
  rather 
  barren. 
  Fossils 
  

   probably 
  present, 
  but 
  not 
  appearing 
  at 
  the 
  surface 
  M. 
  30 
  

  

  2. 
  Shales 
  and 
  sandstone 
  strata, 
  with 
  much 
  checked, 
  iron- 
  

   stained 
  and 
  clayey 
  nodular 
  masses 
  quite 
  similar 
  to 
  

   those 
  yielding 
  Williamsonia 
  casts 
  abundantly 
  some 
  50 
  

   meters 
  further 
  up 
  in 
  the 
  section. 
  There 
  is 
  distinct 
  

   shaly 
  lamination, 
  and 
  sufficiently 
  deep 
  excavation 
  would 
  

   probably 
  reveal 
  fossil 
  plants 
  M. 
  4*6 
  

  

  3.* 
  Indurated 
  and 
  laminated 
  clayey 
  or 
  shaly 
  rock 
  which 
  

   forms 
  sharp 
  ledges 
  in 
  the 
  bed 
  of 
  the 
  barranca. 
  Except 
  

   in 
  a 
  few 
  feet 
  of 
  the 
  lower 
  portion 
  but 
  little 
  softer 
  

   material. 
  Meagerly 
  fossiliferous 
  M. 
  15 
  ± 
  

  

  4.* 
  Another 
  soft 
  but 
  distinctly 
  laminated 
  bed 
  with 
  some 
  

  

  thin 
  sandy 
  layers. 
  Probably 
  fossiliferous 
  M. 
  IT 
  

  

  5. 
  Sandy 
  and 
  clayey 
  to 
  indurated 
  strata, 
  forming 
  ledges 
  

  

  and 
  ending 
  in 
  a 
  horizon 
  with 
  thin 
  seams 
  of 
  coal 
  M. 
  24 
  

  

  6. 
  Contains 
  considerable 
  carbonaceous 
  material 
  interpo- 
  

   lated 
  in 
  clayey 
  and 
  sandy 
  strata. 
  [Dip 
  suddenly 
  

   increases 
  to 
  60.] 
  (Fault 
  of 
  possibly 
  10 
  meters 
  not 
  

   accounted) 
  M. 
  18 
  

  

  7.* 
  Sandstone 
  coal 
  and 
  shale. 
  The 
  record 
  of 
  the 
  u 
  A 
  

   shaft" 
  of 
  Oaxaca 
  Iron 
  and 
  Coal 
  Company 
  includes 
  

   this 
  horizon 
  as 
  follows, 
  measuring 
  from 
  above 
  down- 
  

   ward 
  : 
  — 
  " 
  [25 
  feet 
  of 
  surface 
  wash] 
  ; 
  carbonaceous 
  

   shale, 
  6 
  feet 
  ; 
  coal 
  with 
  clay 
  ' 
  horses,' 
  2| 
  feet 
  ; 
  car- 
  

   bonaceous 
  shale, 
  3 
  feet 
  ; 
  hard 
  calcareous 
  or 
  argillaceous 
  

   or 
  marly 
  shale, 
  2^ 
  feet 
  ; 
  coal 
  with 
  ' 
  horses,' 
  If 
  feet 
  ; 
  cal- 
  

   careous 
  shale, 
  2f 
  feet 
  ; 
  coal, 
  f 
  foot 
  ; 
  carbonaceous 
  shale, 
  

   3 
  feet 
  ; 
  calcareous 
  shales 
  with 
  interpolated 
  carbonace- 
  

   ous 
  or 
  coaly 
  layers, 
  15 
  feet." 
  Total 
  ._ 
  M. 
  19 
  

  

  The 
  strata 
  of 
  No. 
  7 
  are 
  very 
  rich 
  in 
  fossils. 
  JVoeg- 
  

   gerathio])sis 
  and 
  Alethopteris 
  with 
  Otozamites 
  Man- 
  

   delslohi, 
  and 
  the 
  Otozamites 
  Molinianus 
  series, 
  were 
  

   all 
  derived 
  from 
  this 
  horizon. 
  Tcmiopteris, 
  so 
  remark- 
  

   ably 
  abundant 
  in 
  the 
  Yaqui 
  river 
  Trias 
  of 
  Sonora, 
  

   and 
  in 
  the 
  valley 
  of 
  the 
  Nochixtlan 
  river, 
  is 
  here 
  curi- 
  

   ously 
  scarce. 
  

  

  f 
  Various 
  references 
  to 
  plates 
  of 
  the 
  memoir 
  later 
  to 
  appear 
  in 
  Spanish 
  are 
  

   retained. 
  

  

  