﻿318 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  exceptionally 
  perfect 
  specimen 
  turning 
  up 
  at 
  any 
  moment, 
  which 
  

   may 
  afford 
  the 
  key 
  to 
  unsolved 
  problems. 
  The 
  commonly 
  de- 
  

   spised 
  " 
  fish-fragments 
  " 
  are 
  therefore 
  entitled 
  to 
  greater 
  respect 
  

   than 
  most 
  collectors 
  have 
  allowed, 
  and 
  by 
  all 
  means 
  should 
  find 
  

   their 
  way 
  into 
  repositories 
  where 
  they 
  may 
  be 
  preserved 
  and 
  

   freely 
  consulted. 
  

  

  The 
  chief 
  interest 
  olthe 
  present 
  collection 
  centers 
  in 
  its 
  assort- 
  

   ment 
  of 
  Bothriolepis 
  remains, 
  the 
  appendages 
  and 
  various 
  plates 
  

   of 
  the 
  dermal 
  armor 
  being 
  illustrated 
  by 
  more 
  than 
  a 
  score 
  of 
  

   specimens. 
  The 
  species 
  B. 
  minor 
  was 
  originally 
  described 
  from 
  

   Chemung 
  rocks, 
  and 
  has 
  not 
  been 
  heretofore 
  reported 
  from 
  the 
  

   Catskill 
  formation. 
  The 
  occurrence 
  of 
  a 
  Catskill 
  dinichthyid 
  

   and 
  a 
  spine 
  of 
  Onchus, 
  as 
  well 
  as 
  scales 
  of 
  Holoptychius 
  ameri- 
  

   canus 
  in 
  the 
  Ithaca 
  group 
  are 
  likewise 
  matters 
  of 
  general 
  inter- 
  

   est. 
  The 
  principal 
  " 
  fish-bed 
  " 
  of 
  the 
  Upper 
  Devonian 
  in 
  New 
  

   York 
  and 
  Pennsylvania 
  has 
  been 
  referred 
  by 
  most 
  writers 
  to 
  the 
  

   base 
  of 
  the 
  Catskill, 
  though 
  some 
  have 
  placed 
  the 
  line 
  of 
  demar- 
  

   cation 
  higher 
  up, 
  owing 
  to 
  the 
  persistence 
  of 
  typical 
  Chemung 
  

   fossils. 
  At 
  all 
  events 
  it 
  lies 
  near 
  the 
  upper 
  limit 
  of 
  the 
  Chemung 
  

   formation, 
  and 
  in 
  view 
  of 
  the 
  general 
  migration 
  of 
  forms 
  during 
  

   these 
  epochs, 
  it 
  is 
  not 
  surprising 
  that 
  some 
  intermingling 
  of 
  

   species, 
  specially 
  of 
  free-swimming 
  chordates, 
  should 
  be 
  ob- 
  

   served. 
  The 
  New 
  York 
  localities, 
  however, 
  yield 
  a 
  considerably 
  

   smaller 
  number 
  of 
  species 
  than 
  those 
  in 
  the 
  northern 
  tier 
  of 
  

   counties 
  in 
  Pennsylvania. 
  

  

  FISH-FAUNA 
  OF 
  THE 
  ITHACA 
  AND 
  CHEMUNG 
  FORMA- 
  

   TIONS 
  

  

  Family 
  Coccosteidae 
  

  

  Genus 
  dinichthys 
  

  

  The 
  only 
  species 
  of 
  Dinichthys 
  hitherto 
  described 
  from 
  the 
  

   Chemung 
  is 
  D. 
  tuberculatus 
  Newb., 
  founded 
  on 
  detached 
  fragments 
  

   from 
  Warren, 
  Pennsylvania 
  (type 
  in 
  Yale 
  museum). 
  This 
  species 
  

   is 
  remarkable 
  for 
  the 
  relatively' 
  great 
  thickness 
  of 
  its 
  dermal 
  

   plates 
  and 
  their 
  coarsely 
  tuberculate 
  style 
  of 
  ornamentation. 
  

   Fragments 
  that 
  are 
  indistinguishable 
  from 
  those 
  found 
  at 
  the 
  

  

  