﻿48 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  The 
  end 
  of 
  the 
  muzzle 
  was 
  broken 
  from 
  a 
  part 
  or 
  the 
  whole 
  of 
  the 
  cranium, 
  which 
  has 
  not 
  been 
  rediscovered, 
  

   though 
  Dr. 
  Turner 
  has 
  made 
  careful 
  search. 
  It 
  was 
  found 
  in 
  front 
  of 
  the 
  vertebrae 
  here 
  regarded 
  as 
  cervical, 
  at 
  some 
  

   distance 
  from 
  them. 
  

  

  The 
  whole 
  skeleton 
  has 
  been 
  under 
  considerable 
  pressure, 
  so 
  that 
  most 
  of 
  the 
  ribs 
  have 
  been 
  pressed 
  flat 
  on 
  the 
  

   vertebrae; 
  the 
  long 
  parapophyses 
  of 
  the 
  cervicals 
  have 
  most 
  of 
  them 
  been 
  fractured 
  at 
  their 
  bases 
  and 
  compressed, 
  

   those 
  of 
  opposite 
  sides 
  thus 
  approaching 
  more 
  nearly 
  in 
  the 
  form 
  of 
  chevron 
  bones 
  than 
  they 
  otherwise 
  would 
  have 
  

   done. 
  The 
  proximal 
  cervicals 
  are 
  obliquely 
  flattened 
  by 
  the 
  pressure; 
  the 
  other 
  cervicals 
  have 
  the 
  bodies 
  naturally 
  

   flat, 
  with 
  the 
  articular 
  surfaces 
  much 
  less 
  so 
  than 
  the 
  median 
  portion. 
  Some 
  of 
  the 
  caudals 
  are 
  obliquely 
  distorted. 
  

  

  Description 
  — 
  Vertebra. 
  — 
  The 
  neck 
  may 
  be 
  safely 
  assumed 
  as 
  a 
  point 
  of 
  departure, 
  as 
  it 
  consists 
  of 
  above 
  sixty 
  

   mostly 
  continuous 
  vertebrae, 
  which 
  graduate 
  to 
  an 
  atlas 
  of 
  very 
  slender 
  proportions. 
  Most 
  of 
  them 
  preserve 
  more 
  or 
  

   less 
  developed 
  parapophyses. 
  At 
  the 
  posterior 
  extremity 
  of 
  this 
  series, 
  sixteen 
  are 
  perfectly 
  continuous, 
  and 
  in 
  this 
  

   portion 
  a 
  great 
  gradation 
  in 
  form 
  is 
  apparent. 
  The 
  anterior 
  are 
  narrow, 
  compressed, 
  and 
  similar 
  to 
  the 
  more 
  distal 
  

   cervicals 
  in 
  the 
  elevated 
  position 
  of 
  the 
  lateral 
  angle; 
  the 
  anterior 
  are 
  subquadrate, 
  thick, 
  and 
  with 
  lower 
  lateral 
  rib, 
  

   and 
  stronger 
  ? 
  pleurapophysis. 
  In 
  these 
  respects 
  the 
  latter 
  resemble 
  the 
  dorsals 
  which 
  follow, 
  towards 
  what 
  I 
  believe 
  

   to 
  be 
  the 
  tail. 
  Four 
  anterior 
  dorsals 
  are 
  in 
  one 
  mass 
  (figured 
  in 
  plate 
  3) 
  ; 
  in 
  this 
  series 
  the 
  lateral 
  angle 
  first 
  approach- 
  

   ing, 
  is 
  finally 
  lost 
  in 
  the 
  margin 
  of 
  the 
  rib-pit, 
  the 
  posterior 
  thus 
  resembling 
  other 
  dorsals. 
  There 
  can 
  be 
  so 
  far 
  little 
  

   doubt 
  that 
  the 
  anterior 
  and 
  posterior 
  extremities 
  of 
  the 
  masses 
  are 
  correctly 
  interpreted. 
  

  

  In 
  a 
  series 
  of 
  four 
  anterior 
  dorsals, 
  which 
  like 
  the 
  preceding, 
  are 
  in 
  their 
  original 
  continuous 
  mass, 
  those 
  of 
  one 
  

   extremity 
  have 
  centra 
  rounded 
  in 
  section, 
  with 
  inferior 
  rib-pits; 
  those 
  of 
  the 
  other 
  have 
  quadrate 
  centra 
  and 
  elevated 
  

   diapophyses; 
  the 
  former 
  have 
  the 
  character 
  of 
  the 
  first 
  dorsals, 
  the 
  latter 
  of 
  the 
  median 
  dorsals. 
  The 
  posterior 
  dor- 
  

   sals 
  and 
  anterior 
  caudals 
  form 
  in 
  like 
  manner 
  a 
  continuous 
  series 
  of 
  eleven 
  vertebrae, 
  fractured 
  in 
  four 
  places. 
  In 
  

   them 
  the 
  diapophyses 
  steadily 
  descend, 
  reaching 
  the 
  inferior 
  plane 
  in 
  the 
  last, 
  thus 
  with 
  the 
  reduction 
  of 
  the 
  venous 
  

   foramina 
  to 
  one, 
  at 
  the 
  seventh, 
  indicating 
  the 
  point 
  of 
  transition 
  from 
  dorsal 
  to 
  caudal 
  series. 
  The 
  zygapophyses 
  

   preserve 
  the 
  usual 
  arrangement, 
  but 
  are 
  much 
  compressed, 
  so 
  that 
  the 
  posterior 
  or 
  down-looking, 
  are 
  confluent, 
  and 
  

   scarcely 
  separated 
  by 
  an 
  emargination. 
  

  

  The 
  neural 
  spines 
  at 
  their 
  bases 
  have 
  a 
  slight 
  posterior 
  obliquity, 
  and 
  the 
  superior 
  portion 
  leans 
  strongly 
  in 
  the 
  

   anterior 
  direction. 
  The 
  inferior 
  limbs 
  of 
  the 
  cervical 
  pleurapophyses 
  appear 
  to 
  be 
  entirely 
  wanting. 
  The 
  articular 
  

   faces 
  for 
  the 
  chevron 
  bones 
  are 
  seen 
  at 
  the 
  extremity 
  of 
  the 
  inferior 
  rib 
  of 
  the 
  caudal. 
  

  

  Of 
  the 
  cervicals 
  there 
  are 
  both 
  axis 
  and 
  atlas. 
  Of 
  the 
  caudals, 
  probably 
  the 
  distal 
  half, 
  at 
  least, 
  is 
  lost. 
  A 
  single 
  

   vertebra 
  near 
  the 
  middle 
  does 
  not 
  relate 
  to 
  either 
  of 
  those 
  anterior 
  or 
  posterior 
  to 
  it. 
  There 
  are, 
  therefore, 
  at 
  least 
  

   four 
  lost 
  from 
  that 
  region 
  also. 
  

  

  There 
  is 
  a 
  considerable 
  interruption 
  immediately 
  anterior 
  to 
  the 
  last 
  dorsal 
  vertebra. 
  Three 
  large 
  vertebrae, 
  with 
  

   long 
  diapophyses, 
  belonging 
  here, 
  were 
  imbedded 
  in 
  the 
  hard 
  matrix 
  which 
  protected 
  the 
  pelvic 
  arch. 
  These 
  

   are 
  far 
  from 
  relating 
  immediately 
  to 
  the 
  vertebrae 
  preserved 
  before 
  and 
  behind 
  them. 
  I 
  estimate 
  the 
  number 
  missing 
  

   as 
  follows: 
  Seven 
  of 
  the 
  fourteen 
  dorsals 
  preserved 
  have 
  more 
  or 
  less 
  elongate 
  diapophyses. 
  In 
  the 
  Plesiosauri, 
  

   vertebrae 
  of 
  this 
  character, 
  are 
  much 
  more 
  numerous 
  ; 
  in 
  P. 
  homalospondylus 
  Owen 
  gives 
  seventeen. 
  If 
  we 
  add 
  

   ton 
  to 
  the 
  series 
  in 
  the 
  present 
  species 
  it 
  will 
  give 
  the 
  abdominal 
  space 
  between 
  the 
  adjacent 
  margins 
  of 
  the 
  o. 
  o. 
  pubis 
  

   and 
  coracoidea 
  an 
  extent 
  equal 
  to 
  the 
  length 
  of 
  the 
  pelvic 
  arch. 
  This 
  is 
  relatively 
  shorter 
  than 
  in 
  the 
  Plesiosauri. 
  

   Dr. 
  Turner 
  found 
  that 
  a 
  space 
  of 
  " 
  three 
  or 
  four" 
  feet 
  intervened 
  between 
  the 
  two 
  portions 
  of 
  the 
  skeleton, 
  which 
  was 
  

   otherwise 
  continuous. 
  I 
  think 
  ten 
  an 
  average 
  number 
  to 
  represent 
  safely 
  the 
  missing 
  dorsals. 
  

  

  From 
  the 
  cervical 
  proximal 
  regions 
  probably 
  three 
  vertebrae 
  are 
  missing 
  from 
  two 
  interruptions. 
  The 
  remainder 
  

   of 
  the 
  cervical 
  series 
  exhibits 
  three 
  interruptions. 
  Most 
  of 
  the 
  proxirnals 
  have 
  been 
  broken 
  medially, 
  leaving 
  the 
  

   ticulations 
  solid, 
  an 
  advantage 
  in 
  determining 
  their 
  continuity. 
  Three 
  vertebrae 
  and 
  one-half 
  are 
  thus 
  found 
  to 
  be 
  

   missing 
  in 
  this 
  region. 
  

  

  The 
  whole 
  number 
  of 
  vertebra} 
  preserved 
  and 
  lost, 
  with 
  the 
  relative 
  lengths 
  of 
  each, 
  may 
  be 
  stated 
  as 
  follows: 
  

  

  