﻿NO. 
  1969. 
  FOVR 
  NEW 
  SPECIES 
  OF 
  FOSSIL 
  HORSES— 
  HAY. 
  

  

  677 
  

  

  lacking 
  to 
  some 
  extent 
  on 
  the 
  sides 
  and 
  middle 
  of 
  the 
  face 
  and 
  here 
  and 
  

   there 
  in 
  other 
  places; 
  but 
  the 
  stracture 
  of 
  the 
  essential 
  parts 
  is 
  evident. 
  

   Other 
  remains 
  of 
  evidently 
  the 
  same 
  horse 
  have 
  been 
  collected 
  at 
  

   Hay 
  Springs 
  and 
  the 
  neighboring 
  region 
  for 
  the 
  United 
  States 
  

   National 
  Museum 
  and 
  the 
  American 
  Museum 
  of 
  Natural 
  History, 
  in 
  

   New 
  York. 
  Some 
  of 
  these 
  were 
  identified 
  by 
  Mr. 
  Gidley 
  as 
  Equus 
  

   complicatus,^ 
  and 
  the 
  left 
  side 
  of 
  the 
  upper 
  jaw 
  of 
  one 
  specimen, 
  

   No. 
  2725, 
  was 
  figured 
  ^ 
  under 
  this 
  name. 
  In 
  the 
  same 
  paper 
  ^ 
  Mr. 
  

   Gidley 
  figured 
  and 
  identified 
  as 
  E. 
  complicatus 
  the 
  left 
  upper 
  cheek 
  

   teeth 
  of 
  a 
  specimen 
  which 
  he 
  had 
  found 
  in 
  the 
  canyon 
  of 
  Tule 
  Creek, 
  

   in 
  Swisher 
  County, 
  Texas. 
  This 
  specimen 
  likewise 
  appears 
  to 
  belong 
  

   to 
  E. 
  niohrarensis. 
  

  

  It 
  is 
  proper 
  to 
  say 
  here 
  that 
  before 
  the 
  writer 
  began 
  to 
  study 
  the 
  

   skull 
  here 
  described 
  Mr. 
  Gidley 
  had 
  recognized 
  it 
  as 
  belonging 
  to 
  an 
  

   undescribed 
  species. 
  

  

  Below 
  are 
  found 
  measurements 
  which 
  have 
  been 
  taken 
  from 
  the 
  

   skuU, 
  No. 
  4999, 
  United 
  States 
  National 
  Museum. 
  In 
  another 
  column 
  

   are 
  presented 
  corresponding 
  measurements 
  taken 
  on 
  the 
  skull 
  of 
  a 
  do- 
  

   mestic 
  horse. 
  No. 
  843, 
  of 
  the 
  United 
  States 
  National 
  Museum. 
  The 
  

   age 
  of 
  the 
  latter 
  seems 
  to 
  have 
  been 
  about 
  6 
  years, 
  while 
  the 
  Nio- 
  

   brara 
  horse 
  appears 
  to 
  have 
  been 
  approximately 
  a 
  year 
  younger. 
  As 
  

   the 
  lower 
  jaw 
  of 
  the 
  skull. 
  No. 
  843, 
  of 
  the 
  domestic 
  horse 
  is 
  missing, 
  

   measurements 
  of 
  this 
  part 
  are 
  supplied 
  from 
  No. 
  174960 
  of 
  the 
  

   United 
  States 
  National 
  Museum, 
  a 
  large 
  gelding, 
  whose 
  skuU 
  has 
  a 
  

   length 
  of 
  640 
  mm. 
  The 
  upper 
  row 
  of 
  cheek 
  teeth, 
  however, 
  measures 
  

   the 
  same 
  as 
  in 
  No. 
  843. 
  

  

  Measurements 
  of 
  skull 
  in 
  millimeters. 
  

  

  E. 
  niobra- 
  

   rensis. 
  

  

  From 
  middle 
  of 
  incisive 
  border 
  to 
  front 
  of 
  foramen 
  magnum 
  

  

  From 
  middle 
  of 
  incisive 
  border 
  to 
  front 
  of 
  posterior 
  nares 
  . 
  

  

  From 
  middle 
  of 
  incisive 
  border 
  to 
  rear 
  of 
  notch 
  between 
  nasal 
  and 
  premaxiUsc 
  

  

  From 
  middle 
  of 
  incisive 
  border 
  to 
  rear 
  of 
  occipital 
  crest 
  

  

  From 
  middle 
  of 
  incisive 
  border 
  to 
  front 
  of 
  prre.' 
  

  

  From 
  middle 
  of 
  incisive 
  border 
  to 
  front 
  of 
  orbit 
  

  

  Width 
  across 
  mastoid 
  processes 
  

  

  Width 
  across 
  hinder 
  nares 
  

  

  Width 
  across 
  articulation 
  for 
  lower 
  jaw 
  

  

  Width 
  from 
  outside 
  to 
  outside 
  of 
  last 
  molars 
  

  

  Width 
  from 
  outside 
  to 
  outside 
  of 
  outer 
  incisors 
  

  

  Distance 
  between 
  fronts 
  of 
  orbits 
  

  

  Distance 
  between 
  the 
  rear 
  of 
  the 
  orbits 
  

  

  Width 
  of 
  skull 
  on 
  maxillary 
  ridge 
  at 
  maxillo-malar 
  suture 
  

  

  Width 
  of 
  palate 
  at 
  last 
  molars 
  

  

  Width 
  of 
  palate 
  at 
  pm.'^ 
  

  

  Distance 
  across 
  premaxihae 
  at 
  middle 
  of 
  nasal 
  opening 
  

  

  Least 
  width 
  of 
  space 
  between 
  i.' 
  and 
  pm.^ 
  , 
  

  

  Distance 
  between 
  i 
  .^ 
  and 
  pm.'^ 
  

  

  Diameter 
  of 
  orbit, 
  fore 
  and 
  aft 
  

  

  From 
  front 
  of 
  lower 
  jaw 
  to 
  rear 
  of 
  ascending 
  ramus 
  

  

  Length 
  of 
  symphysis 
  of 
  lower 
  jaw 
  

  

  Height 
  of 
  jaw 
  at 
  front 
  of 
  m. 
  i 
  

  

  Rear 
  of 
  i. 
  3 
  to 
  front 
  of 
  pm. 
  2 
  

  

  iBuU.Amer.Mus.Nat.Hist.,T0l.l4,p.l32. 
  'Idem., 
  pi. 
  18, 
  fig. 
  B. 
  

   69077°— 
  Proc.N.M.vol.44— 
  13 
  37 
  

  

  196 
  

   602 
  

   143 
  

   362 
  

   129 
  

   65 
  

   213 
  

   127 
  

   75 
  

   153 
  

   220 
  

   188 
  

   77 
  

   53 
  

   67 
  

   46 
  

   110 
  

   70 
  

  

  'Page 
  132, 
  fig. 
  22. 
  

  

  