﻿F. 
  B. 
  Loomis 
  — 
  Amphibian 
  from 
  the 
  Eocene. 
  219 
  

  

  along 
  the 
  outer 
  margin 
  (acrodont) 
  ; 
  and 
  probably 
  

   extended 
  onto 
  the 
  premaxillae, 
  which 
  are 
  lacking 
  though 
  

   indicated. 
  Inside 
  these 
  are 
  several 
  tiny 
  teeth 
  indicating 
  

   a 
  second 
  inner 
  row, 
  of 
  much 
  smaller 
  size. 
  The 
  palate 
  is 
  

   strongly 
  arched 
  for 
  an 
  amphibian, 
  its 
  anterior 
  portion 
  

   being 
  roofed 
  by 
  the 
  vomers, 
  each 
  of 
  which 
  has 
  a 
  tiny 
  tooth 
  

   on 
  the 
  front 
  margin. 
  On 
  the 
  posterior 
  border 
  of 
  the 
  

   vomers, 
  open 
  the 
  posterior 
  choanen 
  ; 
  and 
  from 
  this 
  point 
  

   back 
  the 
  palate 
  is 
  even 
  more 
  arched. 
  The 
  palatal 
  bones 
  

   are 
  strongly 
  arched 
  and 
  unusually 
  wide, 
  extending 
  back 
  

   in 
  this 
  specimen 
  to 
  beyond 
  the 
  middle 
  of 
  the 
  skull 
  ; 
  and 
  

   possibly 
  the 
  pointed 
  rear 
  ends 
  are 
  missing. 
  The 
  

   arrangement 
  of 
  the 
  vomers, 
  palatines, 
  and 
  the 
  choanen 
  is 
  

   most 
  like 
  that 
  of 
  the 
  newts, 
  especially 
  in 
  the 
  extended 
  

   palatals, 
  in 
  the 
  development 
  of 
  the 
  choanen, 
  and 
  in 
  the 
  

   arching 
  of 
  the 
  palate. 
  Still 
  it 
  is 
  not 
  close 
  enough 
  to 
  

   Triton 
  so 
  that 
  I 
  would 
  want 
  to 
  put 
  it 
  in 
  the 
  same 
  genus. 
  

   The 
  parasphenoid 
  is 
  of 
  moderate 
  size, 
  and 
  it 
  tends 
  to 
  be 
  

   confluent 
  with 
  the 
  exoccipitals 
  and 
  otic 
  bones, 
  but 
  faint 
  

   suture 
  lines 
  indicate 
  the 
  boundaries 
  I 
  have 
  shown 
  in 
  fig. 
  

   1 
  B. 
  The 
  back 
  part 
  of 
  one 
  of 
  the 
  pterygoids 
  is 
  present 
  

   and 
  this 
  is 
  separate 
  from 
  the 
  palatal 
  bones 
  entirely. 
  

  

  The 
  two 
  occipital 
  condyles 
  are 
  confluent 
  and 
  completely 
  

   ossified, 
  making 
  a 
  saddle-like 
  articulation 
  for 
  the 
  skull. 
  

   The 
  whole 
  otic 
  region 
  is 
  completely 
  ossified 
  and 
  strongly 
  

   developed. 
  The 
  inner 
  ear 
  chamber 
  has 
  inflated 
  the 
  otic 
  

   bones 
  so 
  that 
  they 
  have 
  developed 
  a 
  stout 
  process 
  

   around 
  it, 
  on 
  the 
  out 
  end 
  of 
  which 
  is 
  the 
  stapes, 
  wholly 
  

   ossified, 
  and 
  in 
  place 
  on 
  the 
  left 
  side, 
  though 
  lost 
  on 
  the 
  

   right. 
  The 
  epiotic 
  also 
  is 
  largely 
  inflated 
  and 
  develops 
  

   into 
  strong 
  lateral 
  knobs 
  from 
  which 
  the 
  squamosum 
  

   starts. 
  

  

  The 
  back 
  end 
  of 
  the 
  lower 
  jaw 
  is 
  present 
  and 
  of 
  typical 
  

   caudate 
  pattern, 
  but 
  there 
  is 
  not 
  enough 
  of 
  it 
  to 
  offer 
  

   any 
  basis 
  for 
  comparisons. 
  

  

  Amherst 
  College, 
  Amherst, 
  Mass. 
  

  

  