﻿198 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  MOSASAURUS 
  BRUMBYI, 
  Gibbes. 
  

  

  Amphorosteus 
  brumby 
  i, 
  Gibbes. 
  Smithsonian 
  Contrib. 
  to 
  Knowledge, 
  II. 
  9 
  Tab.; 
  Ill, 
  10-16, 
  p. 
  10. 
  

  

  Vertebrae 
  of 
  this 
  species 
  indicate 
  a 
  reptile 
  of 
  larger 
  size 
  than 
  the 
  M. 
  depressus, 
  and 
  approaching 
  the 
  M. 
  dekayi. 
  

   The 
  position 
  of 
  the 
  diapophyses 
  is 
  rather 
  more 
  anterior 
  than 
  in 
  others, 
  and 
  the 
  centrum 
  of 
  the 
  hvmbars 
  rather 
  more 
  

   elongate 
  than 
  in 
  any 
  other 
  species 
  of 
  the 
  genus. 
  The 
  articular 
  extremities 
  are 
  slightly 
  oblique 
  to 
  the 
  vertical 
  diam- 
  

   eter. 
  The 
  animal 
  appears 
  to 
  be 
  not 
  uncommon 
  in 
  the 
  white 
  cretaceous 
  limestone 
  of 
  Alabama. 
  It 
  was 
  first 
  made 
  

   known 
  by 
  Dr. 
  Gibbes, 
  in 
  his 
  Memoir 
  on 
  Mosasaurus 
  and 
  its 
  allies, 
  in 
  the 
  Smithsonian 
  Contribution, 
  Vol. 
  II. 
  

  

  Inches. 
  

   Depth 
  cup, 
  2.05 
  

  

  Width 
  " 
  2.3 
  

  

  Length 
  centrum, 
  3.25 
  

  

  Edge 
  ball 
  to 
  base 
  diapophysis, 
  1.3 
  

  

  Rotten 
  Limestone, 
  upper 
  cretaceous 
  Alabama. 
  

  

  Species 
  of 
  Mosasaurus 
  known 
  only 
  from 
  teetli 
  and 
  cranial 
  hones. 
  

  

  MOSASAURUS 
  CRASSIDENS, 
  Marsh. 
  

   Silliman's 
  Amer. 
  Journ. 
  Sci. 
  Arts, 
  1870 
  (Feb., 
  March). 
  

  

  This 
  species 
  was 
  established 
  on 
  a 
  portion 
  of 
  the 
  maxillary 
  bone 
  with 
  teeth. 
  The 
  latter 
  are 
  peculiar. 
  The 
  crown 
  

   of 
  one, 
  perhaps 
  representative 
  of 
  all, 
  is 
  short, 
  stout, 
  of 
  nearly 
  circular 
  section 
  at 
  the 
  base 
  and 
  compressed 
  towards 
  the 
  

   apex. 
  The 
  latter 
  is 
  obtuse, 
  and 
  furnished 
  on 
  each 
  side 
  with 
  a 
  ridge, 
  which 
  together 
  separate 
  nearly 
  equal 
  faces, 
  and 
  

   do 
  not 
  descend 
  to 
  the 
  base. 
  The 
  apex 
  is 
  slightly 
  rugose; 
  there 
  are 
  no 
  lateral 
  stria? 
  or 
  facets. 
  According 
  to 
  Marsh, 
  

   the 
  maxillary 
  bone 
  is 
  short 
  and 
  deep, 
  and 
  presents 
  a 
  considerable 
  vertical 
  external 
  face. 
  The 
  remains 
  indicate 
  one 
  

   of 
  the 
  largest 
  species 
  of 
  the 
  genus. 
  

  

  From 
  the 
  Cretaceous 
  of 
  North 
  Carolina; 
  discovered 
  by- 
  Prof. 
  Emmons, 
  formerly 
  State 
  Geologist, 
  Mus. 
  AVilliams* 
  

   College, 
  Mass. 
  

  

  MOSASAURUS 
  MINOR, 
  Gibbes. 
  

   Loc. 
  Cit. 
  7 
  Tab. 
  I, 
  3-5. 
  

  

  This 
  small 
  species 
  appears 
  to 
  have 
  been 
  about 
  as 
  large 
  as 
  the 
  Clidastes 
  iguanavus, 
  Cope. 
  

   The 
  Cretaceous 
  of 
  Alabama. 
  

  

  MOSASAURUS 
  COPEANUS, 
  Marsh. 
  

  

  Mosasaurus 
  copeanus. 
  Marsh, 
  Proceedings 
  Amer. 
  Asso. 
  Adv. 
  Sci., 
  1869. 
  Sillim. 
  Amer. 
  Journ. 
  Sci. 
  Arts. 
  1869. 
  393. 
  

  

  The 
  remains 
  which 
  at 
  present 
  represent 
  this 
  species 
  are 
  portions 
  of 
  a 
  skull 
  with 
  some 
  of 
  the 
  maxillary 
  teeth, 
  and 
  

   part 
  of 
  the 
  corresponding 
  lower 
  jaws, 
  including 
  the 
  anterior 
  extremity 
  of 
  the 
  left 
  ramus, 
  and 
  the 
  articular 
  surface 
  of 
  

   the 
  left 
  splenial 
  bone. 
  They 
  indicate 
  one 
  of 
  the 
  smallest 
  Mosasauroids 
  yet 
  discovered, 
  and 
  one 
  very 
  distinct 
  from 
  any 
  

   hitherto 
  known. 
  The 
  teeth 
  are 
  slender, 
  compressed, 
  considerably 
  curved, 
  and 
  deeply 
  facetted. 
  They 
  Sre 
  very 
  

   pointed, 
  and 
  a 
  sharp 
  ridge, 
  without 
  denticulations, 
  divides 
  the 
  outer 
  from 
  the 
  inner 
  surfaces. 
  The 
  enamel 
  of 
  the 
  

   crown 
  is 
  remarkably 
  smooth, 
  and 
  quite 
  unlike 
  the 
  usual 
  corrugated 
  dental 
  surfaces 
  of 
  the 
  larger 
  Mosasauroids. 
  The 
  

   dimensions 
  of 
  a 
  very 
  perfect 
  tooth 
  from 
  near 
  the 
  middle 
  of 
  the 
  left 
  lower 
  jaw 
  are 
  as 
  follows: 
  

  

  Indies. 
  Lines. 
  - 
  

  

  Length 
  of 
  ci-own 
  and 
  osseous 
  support, 
  1 
  n. 
  

  

  Length 
  of 
  crown 
  alone, 
  10.5 
  

  

  Antero-posterior 
  diameter 
  of 
  crown 
  at 
  base, 
  5.25 
  

  

  Transverse 
  diameter 
  of 
  crown 
  at 
  base, 
  4. 
  

  

  