﻿NO. 
  1969. 
  FOUR 
  NEW 
  SPECIES 
  OF 
  FOSSIL 
  HORSES— 
  EAT, 
  571 
  

  

  It 
  belongs 
  to 
  the 
  left 
  side 
  and 
  is 
  taken 
  to 
  be 
  the 
  third 
  or 
  fourth 
  pre- 
  

   molar. 
  Its 
  length 
  is 
  32 
  mm., 
  the 
  width, 
  27.6 
  mm. 
  A 
  third 
  tooth 
  in 
  the 
  

   collection 
  at 
  Yale, 
  found 
  also 
  in 
  South 
  Carolina, 
  and 
  having 
  the 
  

   number 
  11483, 
  is 
  represented 
  by 
  figure 
  3. 
  It 
  is 
  the 
  third 
  or 
  fourth 
  

   right 
  upper 
  premolar. 
  The 
  height 
  of 
  the 
  crown 
  is 
  65 
  mm., 
  the 
  

   length 
  28 
  mm., 
  the 
  width 
  28 
  mm. 
  The 
  enamel 
  is 
  strongly 
  folded. 
  

   A 
  fourth 
  tooth, 
  which 
  belongs 
  to 
  the 
  collection 
  of 
  the 
  Wagner 
  Free 
  

   Institute, 
  Philadelphia, 
  appears 
  to 
  belong 
  with 
  those 
  just 
  described, 
  

   although 
  the 
  enamel 
  is 
  much 
  more 
  plicated 
  than 
  in 
  figures 
  1 
  and 
  2. 
  

   It 
  has 
  the 
  catalogue 
  No. 
  4086, 
  and 
  is 
  one 
  of 
  several 
  teeth 
  col- 
  

   lected 
  along 
  Peace 
  Creek, 
  in 
  1888, 
  by 
  Mr. 
  Joseph 
  Willcox. 
  This 
  

   tooth 
  (fig. 
  4) 
  has 
  the 
  crown 
  72 
  mm. 
  high, 
  31 
  mm. 
  long, 
  and 
  26 
  mm. 
  

   wide. 
  A 
  part 
  of 
  the 
  inner 
  face 
  of 
  the 
  tooth 
  is 
  missing. 
  These 
  teeth 
  

   resemble 
  closely 
  those 
  of 
  E. 
  complicatus, 
  although 
  some 
  of 
  them 
  have 
  

   the 
  enamel 
  little 
  folded. 
  

  

  In 
  the 
  collection 
  of 
  the 
  Wagner 
  Free 
  Institute 
  is 
  a 
  part 
  of 
  a 
  lower 
  

   jaw 
  of 
  a 
  horse 
  of 
  apparently 
  medium 
  or 
  moderately 
  large 
  size. 
  This 
  

   jaw 
  was 
  obtamed 
  by 
  Mr. 
  Willcox 
  on 
  the 
  Caloosahatchie 
  River, 
  

   Florida, 
  in 
  1888. 
  It 
  furnishes 
  the 
  symphysis 
  and 
  a 
  part 
  of 
  the 
  left 
  

   ramus, 
  with 
  the 
  right 
  third 
  incisor, 
  aU 
  the 
  left 
  incisors, 
  and 
  the 
  

   second 
  and 
  third 
  premolars. 
  The 
  animal 
  was 
  young, 
  but 
  mature. 
  

   This 
  jaw 
  was 
  referred 
  to 
  Equus 
  fratemus 
  by 
  Cope.^ 
  According 
  to 
  

   Cope, 
  Doctor 
  Leidy 
  also 
  determined 
  it 
  as 
  Equus 
  fratemus. 
  By 
  Cope 
  

   it 
  was 
  associated 
  with 
  two 
  upper 
  cheek 
  teeth 
  from 
  Peace 
  Creek. 
  

   One 
  of 
  these, 
  whose 
  diameters 
  are 
  given 
  as 
  29 
  mm. 
  and 
  24 
  mm., 
  may 
  

   be 
  the 
  tooth 
  represented 
  here 
  by 
  figure 
  5. 
  The 
  other, 
  not 
  recog- 
  

   nized 
  with 
  certainty, 
  designated 
  by 
  Cope 
  as 
  ''No. 
  2," 
  measured 
  fore 
  

   and 
  aft 
  25 
  mm., 
  traversely 
  26 
  mm. 
  In 
  his 
  measurements 
  of 
  the 
  third 
  

   premolar 
  of 
  the 
  lower 
  jaw 
  Cope 
  gives 
  as 
  the 
  width 
  17 
  mm. 
  It 
  is 
  

   probable 
  that 
  he 
  included 
  the 
  cement. 
  This 
  is 
  not 
  practicable, 
  

   because 
  it 
  is 
  often 
  missing 
  in 
  fossil 
  teeth. 
  

  

  Measurements 
  of 
  the 
  lower 
  jaw. 
  

  

  mm. 
  

  

  Length 
  of 
  the 
  symphysis 
  75 
  

  

  Width 
  of 
  the 
  sjonphysis 
  where 
  narrowest 
  40 
  

  

  Width 
  of 
  the 
  symphysis 
  at 
  third 
  incisors 
  53± 
  

  

  Height 
  of 
  jaw 
  at 
  front 
  of 
  pm..^ 
  60 
  

  

  Height 
  of 
  jaw 
  behind 
  pm.^ 
  82 
  

  

  Distance 
  from 
  i.^ 
  to 
  pm.^ 
  82 
  

  

  Width 
  of 
  1.1 
  16 
  

  

  Width 
  of 
  i.. 
  17 
  

  

  Width 
  of 
  1.3 
  18 
  

  

  Length 
  of 
  grinding 
  surface 
  of 
  pm.2 
  31 
  

  

  Width 
  of 
  grinding 
  surface 
  of 
  pm.., 
  14. 
  5 
  

  

  Height 
  of 
  crown 
  of 
  pjn.^ 
  76 
  

  

  Length 
  of 
  crown 
  of 
  pm.3 
  29 
  

  

  Width 
  of 
  crown 
  of 
  pm.^ 
  15. 
  5 
  

  

  I 
  Proc. 
  Amer. 
  PMlos. 
  Soc, 
  vol. 
  34, 
  p. 
  465. 
  

  

  