﻿Vol. 
  53.] 
  ROCKS 
  AND 
  FOSSILS 
  FROM 
  FKAXZ 
  JOSEF 
  LAND. 
  491 
  

  

  between 
  the 
  other 
  minerals.' 
  The 
  resemblance 
  of 
  this 
  rock 
  to 
  the 
  

   dolerites 
  of 
  Spitsbergen 
  is 
  pointed 
  out, 
  and 
  it 
  is 
  also 
  stated 
  that 
  

   f 
  amygdaloidal 
  varieties, 
  so 
  common 
  in 
  Greenland, 
  were 
  never 
  found 
  

   in 
  Franz 
  Josef 
  Land 
  ; 
  while 
  the 
  rocks 
  in 
  the 
  south 
  were 
  aphanitie 
  

   and 
  thus 
  like 
  true 
  basalts, 
  those 
  in 
  the 
  north 
  were 
  coarse-grained 
  

   and 
  nepheline-bearing.' 
  1 
  From 
  this 
  description 
  we 
  may 
  conclude 
  

   that 
  the 
  rocks 
  brought 
  home 
  by 
  Payer 
  from 
  the 
  eastern 
  portion 
  of 
  

   the 
  archipelago 
  resemble 
  the 
  massive 
  oli 
  vine-bearing 
  varieties 
  of 
  

   the 
  Jackson-Harms 
  worth 
  collection. 
  Prof. 
  Tschermak 
  makes 
  no 
  

   mention 
  of 
  the 
  occurrence 
  of 
  palagonitic 
  material 
  as 
  interstitial 
  

   matter, 
  but 
  he 
  refers 
  to 
  an 
  iron-chlorite 
  which 
  he 
  regards 
  as 
  arising 
  

   from 
  the 
  alteration 
  of 
  olivine. 
  It 
  is 
  possible 
  that 
  this 
  substance 
  

   may 
  in 
  part 
  represent 
  the 
  palagonite 
  so 
  common 
  in 
  the 
  rocks 
  from 
  

   Cape 
  Flora. 
  He 
  speaks 
  of 
  the 
  ; 
  titaniferous 
  iron-ore 
  ' 
  as 
  ' 
  sometimes 
  

   filling 
  the 
  space 
  between 
  the 
  other 
  minerals,' 
  The 
  magnetite 
  in 
  

   the 
  specimen 
  that 
  we 
  examined 
  contained 
  only 
  traces 
  of 
  titanic 
  acid, 
  

   and 
  in 
  none 
  of 
  our 
  rocks 
  does 
  it 
  actually 
  occur 
  as 
  interstitial 
  matter. 
  

   Jt 
  either 
  crystallizes 
  out 
  during 
  the 
  later 
  stages, 
  or 
  else 
  remains 
  

   undifferentiated 
  in 
  the 
  residual 
  glass. 
  Specimens 
  from 
  the 
  northern 
  

   part 
  of 
  the 
  archipelago 
  have 
  not 
  as 
  yet 
  been 
  examined 
  in 
  detail, 
  but 
  

   both 
  Payer 
  and 
  Nansen 
  agree 
  that 
  more 
  coarsely 
  crystalline 
  varieties 
  

   occur 
  in 
  this 
  region. 
  It 
  would 
  be 
  interesting 
  to 
  know 
  the 
  exact 
  

   nature 
  of 
  the 
  evidence 
  on 
  which 
  nephelinehas 
  been 
  stated 
  to 
  occur. 
  

  

  The 
  more 
  or 
  less 
  allied 
  rocks 
  of 
  Spitsbergen 
  have 
  been 
  described 
  by 
  

   A. 
  E. 
  Nordenskiold 
  ~ 
  as 
  hyperite, 
  and 
  by 
  Drasche 
  ;i 
  as 
  diabase. 
  They 
  

   frequently 
  occur 
  as 
  sills 
  in 
  rocks 
  of 
  very 
  variable 
  age. 
  Both 
  authors 
  

   appear 
  to 
  regard 
  them 
  as 
  contemporaneous 
  with 
  the 
  strata 
  in 
  which 
  

   they 
  are 
  found, 
  and 
  Drasche 
  comments 
  on 
  the 
  remarkable 
  nature 
  of 
  

   the 
  fact 
  that 
  rocks 
  so 
  uniform 
  in 
  character 
  should 
  be 
  associated 
  witli 
  

   strata 
  of 
  all 
  ages 
  from 
  pre-Carboniferous 
  to 
  Tertiary. 
  The 
  remarkable 
  

   nature 
  of 
  this 
  fact 
  disappears 
  if 
  we 
  regard 
  the 
  rocks 
  as 
  intrusive 
  

   sills. 
  

  

  A 
  curious 
  difference 
  of 
  opinion 
  has 
  arisen 
  between 
  Backstroin 
  4 
  

   and 
  Nathorst 
  ° 
  as 
  to 
  these 
  Spitsbergen 
  rocks. 
  At 
  the 
  conclusion 
  of 
  

   his 
  paper 
  on 
  the 
  liparites 
  of 
  Iceland, 
  Packstroin 
  calls 
  attention 
  to 
  

   the 
  widespread 
  distribution 
  of 
  basalts 
  in 
  the 
  Arctic 
  province 
  which 
  

   ' 
  extends 
  on 
  the 
  one 
  side 
  to 
  Spitsbergen 
  and 
  Franz 
  Josef 
  Land, 
  on 
  

   the 
  other 
  to 
  Greenland, 
  and 
  in 
  the 
  south 
  to 
  Scotland.' 
  jNathorst, 
  in 
  

   commenting 
  upon 
  this 
  statement, 
  points 
  out 
  that 
  basalt 
  has 
  not 
  been 
  

   found 
  in 
  Spitsbergen, 
  but 
  that 
  post-Triassic 
  diabases 
  occur 
  both 
  as 
  

   dykes 
  and 
  sheets 
  (Deckeu). 
  Whether 
  the 
  Spitsbergen 
  rocks 
  should 
  

   be 
  termed 
  basalts 
  or 
  diabases 
  is 
  a 
  matter 
  of 
  comparatively 
  slight 
  

  

  1 
  ' 
  New 
  Lands 
  within 
  the 
  Arctic 
  Circle,' 
  German 
  ed. 
  p. 
  *267. 
  

  

  2 
  ' 
  Sketch 
  of 
  the 
  Geology 
  of 
  Spitsbergen,' 
  Stockbolm, 
  1867. 
  

  

  3 
  'Petrographisch-geolugische 
  Beobacbtungenan 
  der 
  Westkuste 
  Spitzbergens,' 
  

   Tscherm. 
  Min. 
  Mitth. 
  1874, 
  p. 
  261. 
  

  

  4 
  'Beitrage 
  sur 
  Kenntniss 
  der 
  islandiscben 
  Liparite,' 
  Geol. 
  Foren. 
  Stockholm 
  

   Fbrhandl. 
  vol. 
  xiii. 
  (1891) 
  p. 
  671. 
  

  

  3 
  'Einiges 
  liber 
  die 
  Basalte 
  des 
  arktiscken 
  Gebietes,' 
  ibid. 
  vol. 
  xiv. 
  (1892 
  1 
  ) 
  

   p. 
  69. 
  

  

  