﻿CANYON 
  FERRY 
  FOSSIL 
  VERTEBRATES 
  — 
  ^WHITE 
  423 
  

  

  Merychippus 
  sp. 
  

  

  USNM 
  19095, 
  two 
  fragmentary 
  lower 
  molars, 
  from 
  locality 
  No. 
  

   24LC21. 
  These 
  teeth 
  are 
  too 
  imperfect 
  for 
  specific 
  identification 
  but 
  

   are 
  sufficient 
  to 
  establish 
  the 
  presence 
  of 
  Middle 
  Aliocene 
  deposits 
  in 
  

   this 
  area. 
  

  

  Superfamily 
  BRONTOTHERIOIDEA 
  

  

  At 
  locality 
  No. 
  24LC16 
  a 
  few 
  fragments 
  of 
  teeth 
  referable 
  to 
  the 
  

   large 
  members 
  of 
  this 
  group 
  have 
  been 
  found 
  but 
  they 
  are 
  inadequate 
  

   for 
  even 
  generic 
  reference. 
  

  

  Family 
  Hyracodontidae 
  

  

  USNM 
  19025, 
  right 
  mandibular 
  fragment 
  with 
  dPa-Mi, 
  from 
  locality 
  

   No. 
  24BW18. 
  

  

  Discussion.— 
  'This 
  material 
  is 
  too 
  fragmentary 
  to 
  permit 
  allocation 
  

   to 
  an}^ 
  of 
  the 
  species 
  described 
  from 
  the 
  White 
  River 
  deposits. 
  Sin- 
  

   clair 
  (1922, 
  pp. 
  65-79) 
  recognized 
  four 
  species 
  on 
  the 
  characters 
  of 
  the 
  

   upper 
  premolars 
  and 
  stated 
  (p. 
  67) 
  that 
  no 
  intermediate 
  stages 
  were 
  

   recognized. 
  Scott 
  (1941, 
  p. 
  841) 
  expressed 
  the 
  opinion 
  that 
  there 
  was 
  

   only 
  one 
  valid 
  species 
  of 
  this 
  genus 
  in 
  the 
  White 
  River 
  deposits 
  on 
  

   the 
  grounds 
  that 
  four 
  species 
  of 
  a 
  single 
  genus 
  of 
  large 
  mammals 
  could 
  

   not 
  occupy 
  the 
  same 
  territory 
  equivalent 
  in 
  size 
  to 
  that 
  embraced 
  

   by 
  the 
  White 
  River 
  deposits. 
  On 
  a 
  previous 
  page 
  (p. 
  786) 
  Scott 
  

   quotes 
  Matthew's 
  (1930, 
  pp. 
  271-272) 
  views 
  in 
  connection 
  with 
  the 
  

   species 
  of 
  Trigonias. 
  In 
  his 
  introduction 
  Matthew 
  states 
  that: 
  "We 
  

   do 
  not, 
  in 
  fact, 
  find 
  two 
  or 
  more 
  distinct 
  species 
  or 
  subspecies 
  of 
  a 
  

   genus 
  occupymg 
  the 
  same 
  area 
  and 
  habitat 
  at 
  the 
  same 
  time." 
  This 
  

   statement 
  appears 
  to 
  have 
  been 
  accepted 
  by 
  some 
  workers 
  as 
  an 
  axiom 
  

   but, 
  instead 
  of 
  inspiring 
  caution 
  and 
  the 
  use 
  of 
  recent 
  faunas 
  in 
  inter- 
  

   preting 
  fossil 
  faunas, 
  it 
  has 
  been 
  used 
  as 
  a 
  legitimate 
  excuse 
  for 
  multi- 
  

   plying 
  the 
  number 
  of 
  genera. 
  With 
  the 
  aid 
  of 
  Dr. 
  Henry 
  Setzer 
  of 
  

   the 
  Division 
  of 
  Mammals, 
  U. 
  S. 
  National 
  Museum, 
  I 
  have 
  prepared 
  

   a 
  short 
  list 
  of 
  instances 
  where 
  two 
  or 
  more 
  distinct 
  species 
  of 
  the 
  

   larger 
  mammals 
  occur 
  in 
  the 
  same 
  area 
  and 
  habitat: 
  

  

  Cervidae. 
  — 
  Within 
  historic 
  times 
  the 
  ranges 
  of 
  the 
  Virginia 
  deer 
  {Odocoileus 
  

   virginianus) 
  and 
  the 
  mule 
  deer 
  (0. 
  hemionus) 
  overlapped 
  by 
  nearly 
  a 
  million 
  

   square 
  miles 
  and 
  they 
  occupied 
  the 
  same 
  habitat 
  over 
  the 
  area. 
  No 
  natural 
  

   crosses 
  are 
  known. 
  These 
  forms 
  are 
  morphologically 
  distinct 
  and 
  the 
  skulls 
  and 
  

   horns 
  would 
  be 
  recognizable 
  as 
  fossils. 
  

  

  Canidae. 
  — 
  The 
  above 
  paragraph 
  is 
  true 
  of 
  the 
  wolf 
  {Canis 
  nulilus) 
  and 
  the 
  

   coyote 
  (C 
  latrans). 
  

  

  Equidae. 
  — 
  The 
  horse 
  {Equus 
  caballus) 
  and 
  the 
  ass 
  (E. 
  asinus) 
  ran 
  wild 
  in 
  

   western 
  North 
  America 
  for 
  about 
  300 
  years 
  after 
  escaping 
  from 
  the 
  Spaniards 
  

  

  