﻿572 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol.44. 
  

  

  Figure 
  1, 
  on 
  plate 
  69, 
  represents 
  the 
  little 
  worn 
  incisors 
  of 
  the 
  jaw. 
  

   It 
  has 
  been 
  prepared 
  from 
  a 
  photograph 
  of 
  a 
  cast 
  of 
  the 
  front 
  of 
  the 
  

   jaw. 
  It 
  will 
  be 
  seen 
  that 
  none 
  of 
  the 
  teeth 
  has 
  a 
  complete 
  cup. 
  In 
  

   the 
  first 
  and 
  second 
  incisors 
  the 
  cup 
  is 
  open 
  to 
  the 
  bottom 
  on 
  the 
  

   lingual 
  side; 
  while 
  the 
  third 
  incisor 
  shows 
  only 
  traces 
  of 
  the 
  cup. 
  

   It 
  is 
  this 
  simple 
  condition 
  of 
  the 
  incisors 
  that 
  led 
  Cope 
  to 
  base 
  on 
  

   this 
  jaw 
  his 
  genus 
  Tomolabis} 
  

  

  Figure 
  6 
  shows 
  the 
  arrangement 
  of 
  the 
  enamel 
  in 
  the 
  second 
  and 
  

   third 
  premolars. 
  It 
  is 
  somewhat 
  more 
  complicated 
  than 
  usual 
  in 
  

   the 
  corresponding 
  teeth 
  of 
  species 
  of 
  Equus. 
  

  

  Because 
  (1) 
  of 
  the 
  close 
  resemblance 
  of 
  the 
  type 
  tooth 
  of 
  E.frater- 
  

   nus 
  to 
  the 
  tooth 
  of 
  E. 
  complicatus 
  and 
  the 
  possibility, 
  even 
  probability, 
  

   that 
  these 
  species 
  are 
  identical, 
  and 
  (2) 
  because 
  the 
  incisors 
  of 
  

   E. 
  complicatus 
  are 
  very 
  different 
  from 
  those 
  of 
  the 
  lower 
  jaw 
  in 
  the 
  

   Wagner 
  Free 
  Institute, 
  the 
  writer 
  was 
  at 
  first 
  disposed 
  to 
  refer 
  the 
  

   jaw 
  just 
  mentioned 
  to 
  the 
  species 
  described 
  below 
  as 
  E. 
  leidyi. 
  How- 
  

   ever, 
  the 
  third 
  premolar 
  seems 
  to 
  have 
  the 
  long 
  diameter 
  too 
  great 
  

   to 
  belong 
  with 
  the 
  type 
  tooth 
  of 
  E. 
  leidyi; 
  although 
  perhaps 
  not 
  too 
  

   great 
  to 
  go 
  with 
  the 
  tooth 
  of 
  figure 
  5 
  in 
  case 
  it 
  belongs 
  to 
  E. 
  leidyi. 
  

   Under 
  the 
  circumstances, 
  therefore, 
  it 
  seems 
  best 
  for 
  the 
  present, 
  to 
  

   retain 
  the 
  name 
  of 
  E. 
  fraternus 
  for 
  those 
  larger 
  equine 
  teeth 
  which 
  

   are 
  found 
  along 
  our 
  south 
  Atlantic 
  coast, 
  and 
  which 
  approach 
  more 
  

   or 
  less 
  closely 
  in 
  size 
  and 
  structure 
  the 
  type 
  of 
  this 
  species, 
  as 
  selected 
  

   by 
  Cope; 
  furthermore, 
  to 
  associate 
  with 
  these 
  teeth 
  the 
  lower 
  jaw 
  

   above 
  described, 
  following 
  thus 
  the 
  example 
  of 
  Leidy 
  and 
  Cope. 
  

   This 
  appears 
  to 
  be 
  the 
  more 
  advisable, 
  because 
  in 
  the 
  Peace 
  Creek 
  

   collection 
  there 
  are 
  other 
  lower 
  teeth 
  which 
  it 
  seems 
  necessary 
  to 
  refer 
  

   to 
  E. 
  leidyi, 
  as 
  noted 
  below. 
  It 
  must 
  be 
  said, 
  however, 
  that 
  it 
  seems 
  

   very 
  probable 
  that 
  such 
  teeth 
  as 
  those 
  represented 
  by 
  figures 
  1 
  and 
  2 
  

   represent 
  a 
  species 
  distinct 
  from 
  the 
  typical 
  E. 
  fraternus. 
  

  

  EQUUS 
  LEIDYI, 
  new 
  species. 
  

  

  Type. 
  — 
  One 
  of 
  six 
  teeth 
  in 
  the 
  Wagner 
  Free 
  Institute 
  of 
  Science, 
  

   Philadelphia, 
  which 
  have 
  the 
  catalogue 
  number 
  4086. 
  Found 
  in 
  

   supposed 
  Pleistocene 
  deposits 
  on 
  Peace 
  Creek, 
  Florida. 
  

  

  Characterized 
  by 
  teeth 
  of 
  medium 
  size, 
  the 
  length 
  of 
  the 
  grinding 
  

   surface 
  of 
  the 
  first 
  molar 
  being 
  about 
  25 
  mm., 
  the 
  width 
  about 
  24 
  mm., 
  

   excluding 
  the 
  cement. 
  Enamel 
  surrounding 
  the 
  lakes 
  rather 
  strongly 
  

   folded. 
  Type 
  tooth 
  moderately 
  curved. 
  

  

  This 
  name 
  is 
  intended 
  to 
  designate 
  a 
  horse 
  which 
  possessed 
  teeth 
  

   of 
  medium 
  size, 
  examples 
  of 
  which 
  have 
  been 
  found 
  at 
  various 
  localities 
  

   from 
  North 
  Carolina 
  to 
  Florida. 
  Among 
  these 
  are 
  certain 
  teeth 
  

   figured 
  by 
  Leidy 
  ^ 
  and 
  others 
  by 
  Mr. 
  Gidley. 
  ^ 
  As 
  the 
  special 
  type 
  of 
  

  

  » 
  Proe. 
  Amcr. 
  Philos. 
  Soc, 
  vol. 
  30, 
  p. 
  125; 
  vol. 
  34, 
  p. 
  466. 
  

   2 
  Holmes's 
  Post-Hliocene 
  Foss. 
  S. 
  C, 
  pi. 
  15, 
  figs. 
  S, 
  16. 
  

   « 
  Bull. 
  Amer. 
  Mus. 
  Nat. 
  Hist., 
  vol. 
  14, 
  figs. 
  8, 
  C. 
  D. 
  

  

  