﻿56 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Thence 
  it 
  spread 
  northeastward 
  into 
  Russia, 
  westward 
  into 
  the 
  Eifel 
  

   District, 
  and 
  northwestward 
  into 
  the 
  Hudson 
  and 
  James 
  Bay 
  region. 
  

   From 
  this 
  latter 
  region 
  we 
  may 
  suppose 
  it 
  to 
  have 
  passed 
  south- 
  

   ward 
  through 
  Ontario 
  by 
  means 
  of 
  a 
  passageway 
  connecting 
  with 
  

   the 
  Appalachian 
  gulf 
  over 
  the 
  area 
  that 
  is 
  now 
  occupied 
  by 
  Ohio 
  

   and 
  Indiana, 
  where 
  the 
  fauna 
  reached 
  its 
  climacteric. 
  The 
  most 
  

   conspicuous 
  elements 
  of 
  the 
  fauna 
  are 
  Arthrodires 
  and 
  Ptyctodonts, 
  

   groups 
  which 
  began 
  immediately 
  upon 
  their 
  introduction 
  to 
  attain 
  

   a 
  most 
  remarkable 
  development. 
  Throughout 
  the 
  Hamilton 
  and 
  

   later 
  Devonic, 
  conditions 
  must 
  have 
  been 
  eminently 
  favorable 
  in 
  the 
  

   Appalachian 
  sea 
  for 
  the 
  further 
  specialization 
  of 
  armor-clad 
  Dip- 
  

   noans 
  of 
  the 
  type 
  represented 
  by 
  Dinichthys 
  and 
  its 
  congeners. 
  Like 
  

   their 
  earliest 
  predecessors, 
  they 
  became 
  of 
  greatest 
  importance 
  

   locally 
  in 
  Ohio. 
  

  

  The 
  wide 
  interest 
  to 
  all 
  concerned 
  with 
  the 
  philosophy 
  of 
  paleon- 
  

   tology 
  and 
  the 
  far-reaching 
  significance 
  of 
  such 
  detailed 
  investiga- 
  

   tions 
  as 
  are 
  brought 
  together 
  here, 
  are 
  very 
  effectively 
  set 
  forth 
  in 
  

   the 
  following 
  paragraphs. 
  

  

  There 
  are 
  no 
  other 
  means 
  for 
  attaching 
  significance 
  to 
  a 
  truth 
  

   except 
  by 
  perceiving 
  its 
  relations 
  to 
  other 
  truths. 
  Thus 
  far 
  we 
  have 
  

   been 
  concerned 
  principally 
  in 
  assembling, 
  and 
  to 
  some 
  slight 
  extent 
  

   in 
  correlating 
  recognizable 
  truths 
  ; 
  in 
  a 
  word, 
  facts 
  of 
  observation 
  

   have 
  been 
  brought 
  into 
  orderly 
  array. 
  The 
  next 
  step 
  is 
  to 
  examine 
  

   them 
  in 
  their 
  bearing 
  upon 
  other 
  known 
  facts, 
  to 
  deduce 
  their 
  gen- 
  

   eral 
  significance, 
  and 
  to 
  assign 
  to 
  the 
  results 
  a 
  commensurate 
  worth 
  

   in 
  surveying 
  the 
  whole 
  field 
  of 
  paleontological 
  inquiry. 
  The 
  ulti- 
  

   mate 
  yield 
  of 
  scientific 
  study 
  is 
  the 
  fruition 
  of 
  philosophical 
  ideas. 
  

  

  To 
  obtain 
  a 
  large 
  perspective 
  of 
  the 
  body 
  of 
  facts 
  at 
  our 
  disposal, 
  

   it 
  is 
  desirable 
  to 
  marshal 
  them 
  in 
  different 
  ways, 
  and 
  to 
  examine 
  

   them 
  from 
  different 
  points 
  of 
  view. 
  Their 
  relevancy 
  from 
  a 
  

   geological 
  standpoint 
  needs 
  consideration, 
  with 
  the 
  object 
  of 
  draw- 
  

   ing 
  from 
  them 
  conclusions 
  of 
  geological 
  import. 
  In 
  still 
  larger 
  

   measure 
  it 
  behooves 
  us 
  to 
  consider 
  them 
  as 
  an 
  increment 
  to 
  zoologi- 
  

   cal 
  science, 
  compacting 
  its 
  substantial 
  framework 
  and 
  vastly 
  extend- 
  

   ing 
  our 
  knowledge 
  of 
  the 
  evolutionary 
  history 
  of 
  organisms. 
  Are 
  

   we 
  proposing 
  to 
  ourselves 
  an 
  explanation 
  of 
  life, 
  our 
  vision 
  must 
  

   include 
  not 
  only 
  living 
  matter 
  as 
  we 
  find 
  it 
  today, 
  but 
  also 
  those 
  

   manifestations 
  of 
  it 
  that 
  existed 
  in 
  the 
  remote 
  past. 
  Side 
  by 
  side 
  

   with 
  the 
  development 
  of 
  the 
  individual 
  we 
  must 
  examine 
  the 
  evolu- 
  

   tionary 
  history 
  of 
  the 
  race. 
  The 
  more 
  we 
  learn 
  of 
  vital 
  processes 
  

   now 
  operating, 
  the 
  better 
  able 
  are 
  we 
  to 
  understand 
  their 
  operation 
  

   in 
  times 
  anterior 
  to 
  our 
  own. 
  Comparisons 
  that 
  are 
  enlightening 
  

   when 
  made 
  between 
  members 
  of 
  the 
  modern 
  fauna 
  may 
  often 
  be 
  

   profitably 
  extended 
  so 
  as 
  to 
  include 
  members 
  of 
  extinct 
  faunas. 
  

   Where 
  the 
  time 
  element 
  acts 
  as 
  an 
  impediment 
  to 
  our 
  studies 
  it 
  

   must 
  be 
  eliminated 
  so 
  far 
  as 
  possible. 
  Zoology 
  of 
  the 
  past 
  does 
  not 
  

   differ 
  in 
  essence 
  from 
  zoology 
  of 
  the 
  present, 
  any 
  more 
  than 
  ancient 
  

   history 
  differs 
  fundamentally 
  from 
  modern. 
  

  

  