﻿FOSSIL 
  MARINE 
  FATJ]SrAS 
  KIEK 
  307 
  

  

  to 
  a 
  depth 
  of 
  5,000 
  meters. 
  Of 
  even 
  greater 
  interest 
  is 
  the 
  presence 
  

   of 
  large 
  numbers 
  of 
  colonial 
  corals 
  along 
  the 
  European 
  coast. 
  The 
  dis- 
  

   tribution 
  of 
  these 
  forms 
  has 
  been 
  summarized 
  by 
  Pratje 
  ("Korallen- 
  

   bJinke 
  in 
  tiefem 
  und 
  kiihlem 
  Wasser," 
  Centralbl. 
  f 
  iir 
  Min. 
  Geol. 
  u. 
  Pal. 
  

   1914, 
  No. 
  13, 
  pp. 
  410-415) 
  . 
  He 
  shows 
  that 
  the 
  four 
  species 
  belonging 
  

   to 
  the 
  genera 
  Lophohelia, 
  Amphihelia, 
  and 
  Dendrophyllia 
  referable 
  

   to 
  the 
  families 
  Oculinidse 
  and 
  Eupsammidse 
  are 
  living 
  to-day 
  as 
  far 
  

   as 
  71° 
  north 
  latitude. 
  Off 
  the 
  coast 
  of 
  Norway 
  the 
  bathymetric 
  

   range 
  of 
  the 
  corals 
  is 
  from 
  200 
  meters 
  to 
  GOO 
  meter,s. 
  Oil' 
  the 
  Irish, 
  

   French, 
  and 
  Spanish-Portuguese 
  coasts 
  the 
  optimum 
  depth 
  appears 
  

   to 
  be 
  somewhat 
  the 
  same, 
  but 
  a 
  dowmward 
  range 
  to 
  at 
  least 
  1,800 
  

   meters 
  is 
  known. 
  The 
  seaward 
  range 
  of 
  the 
  corals 
  seems 
  to 
  coincide 
  

   approximately 
  with 
  the 
  edge 
  of 
  the 
  continental 
  shelf. 
  Off 
  the 
  Nor- 
  

   wegian 
  coast 
  with 
  an 
  adver.se 
  factor 
  of 
  high 
  salinity 
  the 
  northern 
  

   limit 
  seems 
  to 
  be 
  conditioned 
  by 
  low 
  temperature. 
  The 
  minimal 
  

   temperature, 
  however, 
  is 
  6.6° 
  C. 
  If 
  the 
  Tetracoralla 
  and 
  Tabulata 
  

   of 
  the 
  past 
  must 
  be 
  considered 
  as 
  requiring 
  temperature 
  and 
  bathy- 
  

   metric 
  conditions 
  like 
  those 
  of 
  present-day 
  corals, 
  we 
  have 
  a 
  wide 
  

   range 
  of 
  both 
  to 
  choose 
  from. 
  

  

  We 
  may 
  now 
  fairly 
  ask 
  the 
  question 
  whether 
  marine 
  animals 
  are 
  

   dependable 
  indicators 
  of 
  the 
  climates 
  of 
  the 
  past. 
  I 
  think 
  this 
  can 
  

   safely 
  be 
  answered 
  in 
  the 
  negative. 
  Most 
  writers 
  consider 
  warm 
  

   climates 
  and 
  warm 
  oceanic 
  waters 
  inseparable, 
  and 
  likewise 
  bracket 
  

   together 
  cold 
  waters 
  and 
  cold 
  climates, 
  overlooking 
  the 
  well-known 
  

   examples 
  of 
  relatively 
  warm 
  waters 
  along 
  coasts 
  in 
  high 
  latitudes 
  

   and 
  cold 
  waters 
  along 
  tropical 
  coasts. 
  Thus 
  the 
  present-day 
  tropical 
  

   climate 
  of 
  coastal 
  Peru, 
  judged 
  by 
  its 
  sub-Antarctic 
  seals, 
  penguins, 
  

   and 
  other 
  cold-water 
  types, 
  would 
  almost 
  certainly 
  be 
  classed 
  as 
  at 
  

   least 
  cold 
  temperate 
  if 
  judged 
  by 
  its 
  fossils. 
  Putting 
  aside 
  atmos- 
  

   pheric 
  temperatures, 
  can 
  we 
  even 
  make 
  accurate 
  temperature 
  read- 
  

   ings 
  of 
  the 
  waters 
  of 
  the 
  ancient 
  seas? 
  Here 
  the 
  factor 
  of 
  depth 
  

   confronts 
  us, 
  but 
  even 
  assuming 
  that 
  all 
  our 
  seas 
  were 
  shallow 
  and 
  

   devoid 
  of 
  currents 
  I 
  still 
  do 
  not 
  think 
  our 
  best 
  efforts 
  in 
  this 
  direc- 
  

   tion 
  would 
  be 
  more 
  than 
  a 
  guess 
  except 
  possibly 
  in 
  the 
  case 
  of 
  our 
  

   later 
  fossil 
  faunas. 
  Life 
  is 
  capable 
  of 
  almost 
  infinite 
  variation 
  and 
  

   adaptation. 
  Thus 
  we 
  see 
  animals 
  changing 
  their 
  habitats 
  from 
  salt 
  

   to 
  fresh 
  water 
  or 
  from 
  normal 
  salt 
  to 
  highly 
  saline 
  water, 
  from 
  

   water 
  to 
  land 
  or 
  from 
  land 
  to 
  water, 
  from 
  cold 
  to 
  hot 
  and 
  from 
  

   hot 
  to 
  cold, 
  in 
  most 
  cases 
  v. 
  hen 
  living 
  in 
  the 
  same 
  medium 
  and 
  ^vithout 
  

   marked 
  structural 
  modifications. 
  As 
  to 
  the 
  evidence 
  to 
  be 
  adduced 
  

   from 
  wide 
  distribution 
  the 
  modern 
  cool 
  and 
  cold 
  water 
  faunas 
  of 
  

   the 
  Southern 
  Hemisphere 
  are 
  quite 
  as 
  widely 
  spread 
  as 
  our 
  Paleozoic 
  

   faunas 
  of 
  the 
  Northern 
  Hemisphere. 
  Some 
  of 
  the 
  Antarctic 
  species 
  

   are 
  even 
  found 
  in 
  the 
  Arctic 
  seas. 
  Distribution 
  after 
  all 
  is 
  pri- 
  

   marily 
  controlled 
  by 
  available 
  routes 
  of 
  travel. 
  

  

  