﻿DESLONGCHAMPS 
  NEW 
  CALEDONIA. 
  31 
  

  

  conformability 
  to 
  older 
  or 
  younger 
  beds, 
  we 
  find 
  not 
  only 
  everywhere 
  

   a 
  marked 
  unconformahility 
  to 
  the 
  Lias, 
  but 
  also 
  a 
  conformability 
  with 
  

   the 
  Keuper, 
  which 
  is 
  nowhere 
  disturbed. 
  

  

  Palaeontology 
  affords 
  evidence 
  of 
  the 
  most 
  intimate 
  relationship 
  of 
  

   the 
  fauna 
  and 
  flora 
  of 
  the 
  Contorta-zone 
  with 
  those 
  of 
  the 
  pre- 
  

   ceding 
  and 
  succeeding 
  strata. 
  Dr. 
  v. 
  Dittmar 
  gives 
  tables 
  showing 
  

   the 
  characteristic 
  fossils 
  of 
  the 
  Contorta-beds 
  and 
  their 
  affinities 
  to 
  

   older 
  and 
  newer 
  forms. 
  From 
  these 
  it 
  appears 
  that, 
  of 
  162 
  species 
  

   which 
  are 
  enumerated, 
  90 
  have 
  allies 
  in 
  the 
  older 
  and 
  72 
  in 
  the 
  

   newer 
  strata, 
  and 
  12 
  species 
  pass 
  through. 
  

  

  Another 
  argument, 
  not 
  strictly 
  a 
  scientific 
  one, 
  though 
  sometimes 
  

   made 
  use 
  of 
  in 
  discussing 
  this 
  question, 
  consists 
  in 
  comparing 
  the 
  

   number 
  of 
  authors 
  who 
  regard 
  this 
  zone 
  as 
  Keuper 
  with 
  those 
  who 
  

   regard 
  it 
  as 
  Liassic. 
  The 
  result 
  of 
  this 
  is 
  not 
  more 
  decisive 
  than 
  that 
  

   obtained 
  from 
  other 
  points 
  of 
  view. 
  Many 
  geologists 
  regard 
  this 
  

   zone 
  as 
  a 
  passage-bed. 
  Such 
  a 
  view 
  is 
  considered 
  by 
  others 
  as 
  most 
  

   impractical 
  and 
  unsatisfactory 
  for 
  systematic 
  purposes. 
  If, 
  however, 
  

   it 
  tends 
  to 
  simplification, 
  and 
  is 
  not 
  unnatural, 
  it 
  ought 
  to 
  be 
  adopted. 
  

   In 
  this 
  case 
  it 
  should 
  be 
  left 
  unconditionally 
  to 
  some 
  high 
  authority 
  

   to 
  fix 
  the 
  boundary. 
  For 
  this 
  reason, 
  as 
  V. 
  Alberti 
  refers 
  the 
  Wiir- 
  

   temberg 
  Bone-bed 
  to 
  the 
  Keuper, 
  and 
  Quenstedt 
  classes 
  it 
  as 
  the 
  

   youngest 
  member 
  of 
  the 
  Trias, 
  the 
  author 
  decides 
  in 
  favour 
  of 
  placing 
  

   the 
  Contorta-zone 
  with 
  the 
  Keuper, 
  the 
  stratigraphical 
  relations 
  of 
  

   the 
  zone 
  also 
  appearing 
  to 
  justify 
  this 
  view. 
  

  

  Dr. 
  von 
  Dittmar 
  concludes 
  by 
  giving 
  a 
  catalogue 
  of 
  the 
  organic 
  

   remains 
  found 
  in 
  the 
  Contorta-beds, 
  with 
  critical 
  remarks 
  thereon. 
  

  

  [F. 
  G. 
  F.] 
  

  

  On 
  the 
  Geology 
  of 
  New 
  Caledonia, 
  and 
  on 
  some 
  Teiassic 
  Fossils 
  

   from 
  the 
  Island 
  of 
  Hugo. 
  By 
  M. 
  Eugene 
  Deslongchamps. 
  

  

  [Documents 
  sur 
  la 
  Greologie 
  de 
  la 
  Nouvelle-Caledonie, 
  suivis 
  du 
  Catalogue 
  des 
  

   roches 
  recueillies 
  dans 
  cette 
  ile 
  par 
  MM. 
  Jouan 
  et 
  Emile 
  Deplanches, 
  et 
  de 
  

   la 
  description 
  des 
  fossiles 
  Triasiques 
  recueillies 
  a 
  l'ile 
  Hugon. 
  Par 
  M. 
  

   Eugene 
  Deslongchamps. 
  Bull. 
  Soc. 
  Linn, 
  de 
  Normandie, 
  vol. 
  viii. 
  pp. 
  332- 
  

  

  378.] 
  

  

  Amongst 
  the 
  rock-specimens 
  collected 
  in 
  the 
  Island 
  of 
  Hugo, 
  near 
  

   New 
  Caledonia, 
  by 
  MM. 
  Deplanches, 
  are 
  some 
  presenting 
  a 
  peculiar 
  

   appearance 
  on 
  account 
  of 
  the 
  immense 
  numbers 
  of 
  an 
  Avicula 
  in 
  

   them. 
  They 
  so 
  nearly 
  resemble 
  A. 
  salinaria, 
  Goldf., 
  that 
  they 
  are 
  

   doubtfully 
  distinguished 
  from 
  that 
  species, 
  and 
  they 
  form 
  the 
  var. 
  

   Richmondiana, 
  Zittel. 
  The 
  rocks 
  of 
  the 
  Island 
  of 
  Hugo 
  resemble 
  in 
  

   every 
  respect 
  those 
  of 
  the 
  Upper 
  Trias 
  of 
  the 
  Alps, 
  at 
  Dorrenberg, 
  

   where 
  the 
  Avicula 
  salinaria 
  is 
  found 
  by 
  myriads 
  ; 
  and 
  although 
  the 
  

   appearance 
  of 
  the 
  New 
  Caledonian 
  rock, 
  the 
  aspect 
  of 
  which 
  resem- 
  

   bles 
  the 
  Devonian 
  Grauwacke, 
  contrasts 
  with 
  the 
  Triassic 
  rocks 
  of 
  

   St. 
  Cassian, 
  Hallstatt, 
  &c, 
  M. 
  Deslongchamps 
  does 
  not 
  hesitate 
  to 
  

   regard 
  the 
  limestone 
  of 
  the 
  Island 
  of 
  Hugo 
  as 
  belonging 
  to 
  the 
  

   Upper 
  Trias. 
  The 
  Avicula 
  is 
  associated 
  with 
  three 
  species 
  of 
  Bra- 
  

  

  