﻿650 
  PR0CEEDIN08 
  OF 
  THE 
  ^\iTIOXAL 
  MVl^EVM. 
  vol.44. 
  

  

  the 
  lumbar, 
  sacral, 
  and 
  anterior 
  caudal 
  vertebrae 
  are 
  quite 
  uniform 
  

   in 
  size 
  and 
  general 
  character, 
  there 
  is 
  good 
  reason 
  for 
  locating 
  the 
  

   sacral 
  region 
  between 
  the 
  thirteenth 
  and 
  seventeenth 
  vertebrae 
  count- 
  

   ing 
  backward 
  from 
  the 
  last 
  thoracic. 
  Not 
  only 
  were 
  the 
  vestigial 
  

   pelvic 
  bones 
  and 
  femur, 
  described 
  by 
  Lucas, 
  found 
  in 
  the 
  rock 
  at 
  

   about 
  this 
  point, 
  but 
  these 
  three 
  vertebrae 
  differ 
  from 
  all 
  the 
  others 
  

   of 
  the 
  series 
  in 
  the 
  modification 
  of 
  the 
  transverse 
  processes, 
  which 
  are 
  

   very 
  noticeably 
  thickened 
  and 
  blunted 
  at 
  their 
  outer 
  ends, 
  their 
  

   appearance 
  suggesting 
  that 
  in 
  some 
  remote 
  ancestral 
  forms 
  these 
  

   processes 
  articulated 
  with 
  the 
  pelvic 
  bones 
  when 
  the 
  pelvis 
  was 
  pro- 
  

   portionately 
  much 
  larger 
  than 
  in 
  the 
  form 
  represented 
  by 
  the 
  present 
  

   specimen. 
  

  

  Considering 
  these 
  vertebrae 
  as 
  sacrals, 
  the 
  vertebral 
  formula 
  for 
  

   the 
  skeleton 
  as 
  restored 
  is, 
  cervicals 
  7, 
  thoracics 
  14, 
  lumbars 
  13, 
  

   sacrals 
  3, 
  and 
  caudals 
  21. 
  

  

  As 
  already 
  mentioned 
  by 
  Lucas,^ 
  the 
  bones 
  in 
  each 
  of 
  these 
  skele- 
  

   tons 
  when 
  found 
  were 
  lying 
  nearly 
  in 
  their 
  natural 
  positions, 
  so 
  that 
  

   there 
  was 
  little 
  or 
  no 
  chance 
  for 
  error 
  in 
  again 
  placing 
  the 
  elements 
  of 
  

   the 
  vertebral 
  column 
  after 
  removal 
  from 
  their 
  original 
  bed. 
  More- 
  

   over, 
  the 
  specimens 
  admirably 
  supplement 
  each 
  other, 
  the 
  ojie 
  com- 
  

   prising 
  the 
  anterior 
  portion 
  of 
  the 
  skeleton 
  ending 
  just 
  behind 
  the 
  

   thoracic 
  region 
  includes 
  but 
  one 
  lumbar 
  vertebra 
  which 
  differs 
  in 
  the 
  

   character 
  of 
  the 
  transverse 
  processes 
  sufficiently 
  to 
  indicate 
  that 
  it 
  is 
  

   not 
  duplicated 
  by 
  the 
  first 
  vertebra, 
  a 
  lumbar, 
  of 
  the 
  second 
  specimen. 
  

   Hence, 
  if 
  any 
  error 
  has 
  been 
  made 
  in 
  the 
  total 
  number 
  of 
  elements 
  

   included 
  in 
  the 
  vertebral 
  column, 
  it 
  is 
  that 
  they 
  are 
  too 
  few 
  rather 
  than 
  

   too 
  many. 
  

  

  The 
  skull 
  (see 
  pi. 
  82) 
  was 
  not 
  complete, 
  but 
  as 
  restored 
  by 
  the 
  

   writer 
  is 
  given 
  a 
  length 
  of 
  about 
  5 
  feet, 
  which 
  length 
  can 
  not 
  be 
  far 
  

   from 
  correct, 
  since 
  the 
  original 
  parts 
  include 
  nearly 
  all 
  the 
  posterior 
  

   portion 
  of 
  the 
  cranium 
  with 
  the 
  glenoid 
  fossae 
  intact 
  and 
  one 
  com- 
  

   plete 
  lower 
  ramus, 
  which 
  portions 
  when 
  properly 
  articulate 
  give 
  

   approximately 
  the 
  true 
  total 
  length 
  of 
  the 
  skull. 
  The 
  snout 
  is 
  greatly 
  

   elongated 
  and 
  the 
  teeth 
  highly 
  specialized, 
  but 
  otherwise 
  the 
  skull 
  

   presents 
  many 
  features 
  of 
  the 
  more 
  primitive 
  carnivores 
  and 
  does 
  not 
  

   in 
  the 
  least, 
  except 
  perhaps 
  in 
  the 
  form 
  of 
  the 
  anterior 
  teeth, 
  suggest 
  

   any 
  of 
  the 
  whales. 
  The 
  lambdoidal 
  crest 
  is 
  greatly 
  expanded 
  for 
  the 
  

   attachment 
  of 
  heavy 
  muscles, 
  and 
  the 
  brain 
  case 
  is 
  comparatively 
  

   large, 
  otherwise 
  the 
  posterior 
  portion 
  of 
  the 
  skull 
  resembles 
  in 
  many 
  

   features 
  that 
  of 
  a 
  large 
  creodont. 
  This 
  has 
  led 
  some 
  good 
  authorities 
  

   to 
  believe 
  that 
  the 
  zeuglodons 
  were 
  descendants 
  of 
  some 
  branch 
  of 
  the 
  

   creodonts. 
  

  

  The 
  fore 
  limbs 
  (see 
  fig. 
  1, 
  p. 
  651) 
  are 
  much 
  modified 
  and 
  in 
  some 
  

   degree 
  cetaceanlike, 
  at 
  least 
  as 
  regards 
  the 
  scapula. 
  The 
  humerus 
  is 
  

  

  » 
  Proc. 
  U. 
  S. 
  Nat. 
  Mus., 
  vol. 
  23, 
  1900, 
  p. 
  321. 
  

  

  