﻿FOURTH 
  REPORT 
  OF 
  THE 
  DIRECTOR 
  1907 
  43 
  

  

  station 
  on 
  the 
  West 
  Shore 
  Railroad. 
  The 
  character 
  of 
  the 
  fauna 
  

   of 
  these 
  Port 
  Ewen 
  beds 
  has 
  not 
  been 
  well 
  understood 
  and 
  it 
  was 
  

   this 
  problem 
  that 
  carried 
  Professor 
  Chadwick 
  into 
  the 
  field. 
  

   Through 
  the 
  efforts 
  of 
  Mr 
  Chadwick 
  and 
  Mr 
  Shinier 
  we 
  have 
  now 
  

   a 
  fairly 
  adequate 
  idea 
  of 
  the 
  composition 
  of 
  the 
  fauna 
  of 
  these 
  beds. 
  

  

  Though, 
  as 
  already 
  stated, 
  the 
  preponderance 
  in 
  the 
  census 
  of 
  the 
  

   species 
  so 
  far 
  as 
  known, 
  is 
  Helderbergian 
  there 
  is 
  a 
  noteworthy 
  

   percentage 
  of 
  species 
  that 
  may 
  be 
  regarded 
  as 
  normal 
  or 
  at 
  least 
  

   usual 
  to 
  the 
  calcareous 
  Oriskany 
  above. 
  Various 
  others 
  have 
  been 
  

   recognized 
  as 
  passing 
  upward 
  from 
  the 
  Helderbergian 
  into 
  this 
  

   Oriskany 
  and 
  Mr 
  Chadwick 
  in 
  his 
  closest 
  analyses 
  of 
  the 
  assem- 
  

   blage 
  has 
  pointed 
  out 
  its 
  generally 
  decadent 
  condition 
  as 
  a 
  Helder- 
  

   berg 
  fauna. 
  

  

  There 
  are 
  also 
  other 
  species 
  of 
  very 
  first 
  import 
  which 
  have 
  and 
  

   probably 
  must 
  continue 
  to 
  be 
  regarded 
  as 
  index 
  fossils 
  of 
  the 
  

   Oriskany 
  formation. 
  Chadwick 
  determines 
  Megalanteris 
  

   ovalis, 
  Beachia 
  suessana, 
  Leptocoelia 
  flabel- 
  

   lites, 
  Leptostrophia 
  oriskania, 
  Brachyprion 
  

   majus 
  and 
  B. 
  schuchertanum. 
  He 
  indicates 
  also 
  the 
  

   possible 
  occurrence 
  of 
  Spirifer 
  arenosus. 
  Professor 
  

   Shimer 
  determines 
  Spirifer 
  murchisoni 
  and 
  M 
  e 
  r 
  i 
  s 
  - 
  

   t 
  el 
  1 
  a 
  lata. 
  

  

  It 
  becomes 
  now 
  a 
  question 
  for 
  very 
  careful 
  consideration 
  whether 
  

   a 
  fauna 
  lying 
  beneath 
  the 
  normal 
  position 
  of 
  the 
  Oriskany 
  beds 
  

   and 
  carrying 
  such 
  fossils 
  as 
  these, 
  can 
  with 
  propriety 
  be 
  regarded 
  

   a 
  Helderbergian 
  fauna 
  notwithstanding 
  its 
  preponderance 
  of 
  Helder- 
  

   berg 
  species. 
  Upon 
  this 
  line 
  of 
  inquiry 
  the 
  recently 
  discovered 
  

   Oriskany 
  fauna 
  already 
  referred 
  to 
  will 
  throw 
  additional 
  light 
  

   but 
  the 
  evident 
  earlier 
  immigration 
  into 
  the 
  eastern 
  New 
  York 
  

   region 
  of 
  Oriskany 
  species 
  than 
  had 
  before 
  been 
  noted 
  is 
  not 
  in 
  

   anywise 
  out 
  of 
  harmony 
  with 
  the 
  evidence 
  of 
  their 
  association 
  

   in 
  the 
  Gaspe 
  basin 
  at 
  the 
  northeast. 
  

  

  Monograph 
  of 
  the 
  Eurypterida. 
  It 
  has 
  long 
  been 
  the 
  writer's 
  

   purpose 
  to 
  prepare 
  a 
  revision 
  of 
  these 
  remarkable 
  crustaceans 
  which 
  

   occur 
  in 
  a 
  variety 
  and 
  abundance 
  in 
  the 
  rocks 
  of 
  New 
  York 
  

   unequaled 
  elsewhere 
  in 
  the 
  world. 
  The 
  Bertie 
  waterlime 
  outcrops 
  

   in 
  Erie, 
  Cayuga 
  and 
  Herkimer 
  counties 
  and 
  the 
  Salina 
  (Pittsford) 
  

   shales 
  in 
  Monroe 
  and 
  Orange 
  counties 
  have 
  now 
  afforded 
  a 
  really 
  

   extraordinary 
  manifestation 
  of 
  the 
  profusion 
  of 
  these 
  creatures. 
  

   Fifty 
  years 
  ago 
  James 
  E. 
  De 
  Kay 
  and 
  Professor 
  Hall 
  had 
  described 
  

   the 
  commoner 
  forms 
  of 
  these 
  crustaceans 
  Eurypterus 
  and 
  Pterygo- 
  

   tus 
  from 
  the 
  Bertie 
  waterlimes, 
  and 
  Messrs 
  Grote 
  and 
  Pitt 
  some 
  

  

  