﻿230 
  lea. 
  s. 
  :r:::z::. 
  :>" 
  ez3£ai>-= 
  or 
  eocz>~z 
  a>™ 
  mxs:z:<ic 
  

  

  B 
  BTH 
  : 
  1 
  KELTS 
  PTLCHEICZJ 
  5 
  . 
  

  

  To 
  the 
  type 
  species 
  I 
  refer 
  the 
  somewhat 
  imperfect 
  and 
  rather 
  

   crushed 
  specimen 
  represented 
  in 
  PI. 
  VIII. 
  figs. 
  1. 
  la. 
  This 
  speci- 
  

   men 
  agrees 
  with 
  the 
  type 
  in 
  the 
  following 
  features, 
  which 
  may 
  he 
  

   taken 
  as 
  diagno 
  stic. 
  S 
  bull 
  much 
  depressed, 
  with 
  prognathous 
  muzzle, 
  

   and 
  a 
  loDg 
  interval 
  between 
  the 
  latter 
  and 
  the 
  tympanum 
  ; 
  nares 
  

   comparatively 
  small 
  and 
  wide 
  ; 
  nasals 
  of 
  moderate 
  size 
  and 
  width 
  ; 
  

   palatal 
  ridges 
  very 
  prominent 
  ; 
  nasal 
  and 
  maxillae 
  uni: 
  __ 
  :: 
  rxclude 
  

   prefrontals 
  from 
  nares. 
  

  

  PlHTSTOCHZLTS 
  CASTABKIGIKKSIS. 
  n. 
  Sp. 
  

  

  The 
  well-preserved 
  cranium 
  in 
  the 
  British 
  Museum 
  No. 
  43980) 
  

   rej 
  resente 
  1 
  in 
  6gs. 
  2, 
  2 
  a 
  of 
  Plate 
  YIH. 
  differs 
  from 
  that 
  of 
  the 
  type 
  

   b 
  pedes 
  in 
  its 
  more 
  vaulted 
  contour, 
  the 
  less 
  produced 
  muzzle, 
  and 
  

   the 
  shorter 
  interval 
  be 
  :^een 
  the 
  latter 
  and 
  the 
  tympanum, 
  as 
  well 
  

   as 
  by 
  the 
  relatively 
  wider 
  nasals. 
  I 
  find 
  a 
  smaller 
  cranium 
  of 
  

   similar 
  type 
  in 
  Mr. 
  Jesson's 
  collection. 
  Assuming 
  these 
  points 
  to 
  be 
  

   ■;: 
  spc 
  sific 
  value, 
  this 
  form 
  maybe 
  known 
  under 
  the 
  above-mentioned 
  

   name. 
  This 
  specimen 
  shows 
  that 
  the 
  auditory 
  labyrinth 
  was 
  open 
  

   posteriorly. 
  

  

  Same 
  :z£lts 
  iLLCBonntrvA. 
  n. 
  ap. 
  

  

  Of 
  this 
  form 
  there 
  are 
  numerous 
  imperfect 
  crania 
  in 
  llr. 
  Jesson's 
  

   collection, 
  while 
  another 
  in 
  the 
  British 
  Museum 
  pSTo. 
  35193), 
  

  

  shown 
  in 
  fig. 
  7 
  of 
  Plate 
  Till., 
  is 
  selected 
  as 
  the 
  type. 
  It 
  is 
  cha- 
  

   racterized 
  by 
  the 
  premaxillge 
  being 
  deeper 
  and 
  less 
  prominent 
  than 
  

   in 
  the 
  type 
  species, 
  by 
  the 
  large 
  and 
  antero-posteriorly 
  elongated 
  

   nasals, 
  the 
  moderate-sized 
  nares, 
  and 
  by 
  the 
  more 
  vaulted 
  cranium 
  

  

  in 
  which 
  the 
  frontal 
  regi:^ 
  is 
  men 
  flattened. 
  

  

  RBIffC 
  EHBEIB 
  EUBGA1TB, 
  D. 
  BD. 
  

  

  The 
  anterior 
  portion 
  of 
  a 
  cranium 
  represented 
  in 
  PI. 
  VJLLL 
  fig. 
  •: 
  

   ( 
  P.M. 
  N 
  : 
  . 
  41796) 
  apparently 
  indicates 
  another 
  species, 
  which 
  attained 
  

   somewhat 
  larger 
  dimensions 
  than 
  either 
  of 
  the 
  preceding, 
  and 
  is 
  

   characterized 
  as 
  follows. 
  Allied 
  to 
  S. 
  macrorh 
  ma, 
  but 
  with 
  the 
  nasals 
  

   relatively 
  wider 
  and 
  shorter, 
  and 
  the 
  premaxilhe 
  considerably 
  deeper. 
  

   The 
  latter 
  character 
  causes 
  the 
  beak 
  to 
  have 
  a 
  decidedly 
  hooked 
  

   appearance. 
  Skulls 
  of 
  the 
  type 
  of 
  the 
  nes: 
  specimen 
  ;hs: 
  show 
  a 
  

   peculiar 
  lateral 
  swelling 
  in 
  the 
  prefrontal 
  regi 
  : 
  n, 
  which 
  appears 
  t 
  : 
  be 
  

   instinctive 
  of 
  this 
  form. 
  

  

  The 
  well-preserved 
  skull 
  shown 
  in 
  fig. 
  4 
  of 
  Plate 
  VJJJL 
  is 
  fit 
  m 
  

   Jesson's 
  ::llection. 
  and 
  apparently 
  indicates 
  an 
  individual 
  belonging 
  

   to 
  the 
  same 
  species 
  as 
  the 
  preceding. 
  Curiously 
  -enough, 
  thetr 
  is, 
  

   however, 
  no 
  trace 
  of 
  a 
  suture 
  between 
  the 
  nasals 
  and 
  prefrontals, 
  

   which 
  at 
  first 
  led 
  me 
  to 
  believe 
  that 
  this 
  specimen 
  belonged 
  to 
  

   Chelone. 
  The 
  peculiar 
  form 
  of 
  the 
  suture 
  t 
  stween 
  the 
  frontals 
  and 
  

   prefrontals 
  shows, 
  however, 
  where 
  the 
  nasal 
  suture 
  should 
  be 
  ; 
  while 
  

   we 
  have 
  the 
  continuaticn 
  : 
  : 
  tl 
  - 
  alveolar 
  line 
  of 
  the 
  maxilla 
  by 
  the 
  

   jngal, 
  which 
  is 
  at 
  nice 
  listinctiTe. 
  

  

  