﻿OSTEOLOGY 
  OF 
  TESTUDO 
  PRAEEXTANS 
  — 
  GILMORE 
  

  

  295 
  

  

  No. 
  ir»72S 
  was 
  foiiiul 
  in 
  1942 
  about 
  a 
  inik" 
  north 
  of 
  Wliitnian 
  Post- 
  

   oflice 
  and 
  consists 
  of 
  carapace, 
  plastron, 
  hunuMus, 
  both 
  scapulae, 
  both 
  

   coracoids, 
  both 
  tii)iao, 
  both 
  fibulao, 
  tarsals, 
  and 
  sonic 
  foot 
  bones; 
  

   specimen 
  I'.S.X.M. 
  Xo. 
  10)732 
  was 
  coUccti'tl 
  in 
  1942 
  on 
  the 
  Anderson 
  

   Kanch 
  on 
  the 
  nortli 
  side 
  of 
  Young 
  Woman 
  Creek 
  and 
  consists 
  of 
  

   carapace, 
  })lastron. 
  pelvis, 
  two 
  humeri, 
  coracoid, 
  two 
  scapulae, 
  tibia, 
  

   two 
  ulnae, 
  two 
  radii, 
  parts 
  of 
  both 
  fibulae, 
  and 
  foot 
  bones. 
  

  

  DESCRIPTION 
  

  

  Skull. 
  — 
  Of 
  the 
  48 
  or 
  more 
  species 
  of 
  Testudo 
  described 
  from 
  North 
  

   America, 
  the 
  skulls 
  of 
  only 
  sLx 
  are 
  known 
  at 
  the 
  present 
  time. 
  These 
  

   are 
  Testudo 
  thom.soni 
  Hay, 
  T. 
  peragrans 
  Hay, 
  T. 
  oshorniana 
  Hay, 
  T. 
  

   impensa 
  Hay, 
  T. 
  orthopygia 
  (Cope), 
  and 
  T. 
  gilberti 
  Hay; 
  and 
  only 
  one 
  

   of 
  these, 
  T. 
  thomsoni, 
  is 
  from 
  the 
  Oligocene. 
  To 
  this 
  list 
  we 
  may 
  now 
  

   add 
  T. 
  jiraeertans 
  Lambe, 
  represented 
  by 
  an 
  unusually 
  well 
  preserved 
  

   skull 
  and 
  lower 
  jaws 
  belonging 
  to 
  specimen 
  U.S.N.M. 
  No. 
  15874 
  and 
  

   illustrated 
  in 
  three 
  views 
  in 
  figures 
  20-22. 
  

  

  Figure 
  21. 
  — 
  Lateral 
  view 
  of 
  skull 
  and 
  lower 
  jaws 
  of 
  Testudo 
  praeextans 
  Lanibc 
  (U.S.N.M. 
  

   No. 
  15874): 
  an, 
  angular; 
  ar, 
  articular; 
  c, 
  coracoid; 
  d, 
  dentary; 
  /, 
  frontal; 
  /, 
  jugai; 
  mx^ 
  

   maxilla; 
  occ, 
  occipital 
  condyle; 
  p, 
  parietal; 
  pf, 
  prefrontal; 
  p7nx, 
  premaxillary; 
  prj, 
  post- 
  

   frontal; 
  qu, 
  quadrate; 
  sa, 
  surangular; 
  so, 
  supraoccipital; 
  sq, 
  squamosal. 
  Natural 
  size. 
  

  

  The 
  skull 
  and 
  lower 
  jaws 
  of 
  this 
  specinicn 
  arc 
  practically 
  complete 
  

   and 
  undistorted, 
  with 
  numy 
  of 
  the 
  cranial 
  sutures 
  clearly 
  distinguish- 
  

   able 
  (fig. 
  21). 
  Th(! 
  skull 
  is 
  of 
  moderate 
  size. 
  Its 
  length, 
  from 
  the 
  tip 
  

   of 
  the 
  premaxillary 
  to 
  the 
  occipital 
  condyle, 
  is 
  81 
  mm.; 
  its 
  width 
  across 
  

   the 
  sf|UHinosals 
  is 
  57 
  mm.; 
  the 
  height 
  from 
  tiie 
  cutting 
  edge 
  of 
  the 
  

   mu.xiila 
  to 
  the 
  upper 
  surface 
  of 
  the 
  frontal 
  is 
  2\\ 
  mm. 
  'V\\v. 
  sides 
  of 
  the 
  

   skull 
  forward 
  to 
  the 
  backs 
  of 
  the 
  orbits 
  arc 
  ncniiy 
  parallel; 
  beyond 
  

   here 
  tliev 
  regtdarly 
  converge 
  to 
  the 
  broadly 
  rounded 
  snout. 
  Viewed 
  

   from 
  the 
  side 
  tiie 
  upper 
  outline 
  of 
  the 
  skull 
  is 
  nearly 
  straight 
  to 
  a 
  i)oint 
  

   above 
  the 
  anterior 
  borders 
  of 
  the 
  orbits 
  where 
  the 
  prefrontals 
  bend 
  

   strongly 
  downward. 
  

  

  