﻿AND 
  AVES 
  OF 
  NORTH 
  AMERICA. 
  65 
  

  

  The 
  most 
  perfect 
  tooth 
  is 
  slender 
  and 
  curved, 
  and 
  bears 
  much 
  resemblance 
  to 
  those 
  of 
  Holops 
  obscurus. 
  

   The 
  section 
  of 
  both 
  root 
  and 
  crown 
  circular, 
  the 
  latter 
  regularly 
  acuminate, 
  and 
  furnished 
  with 
  delicate 
  cutting 
  

   ridges. 
  Terminal 
  half 
  smooth, 
  basal 
  half 
  with 
  a 
  silky 
  striation. 
  Fang 
  as 
  well 
  as 
  crown 
  strongly 
  curved. 
  Cutting 
  

   ridge 
  descending 
  as 
  far 
  on 
  the 
  posterior, 
  as 
  the 
  anterior 
  aspect 
  of 
  the 
  crown. 
  In 
  a 
  fractured 
  New 
  Jersey 
  tooth, 
  I 
  

   count 
  three 
  dentinal 
  cones. 
  In 
  one 
  from 
  Maryland, 
  four. 
  The 
  inner 
  cone 
  is 
  weakly 
  fluted 
  in 
  both, 
  but 
  it 
  scarcely 
  

   affects 
  the 
  form 
  of 
  the 
  enamel. 
  

  

  The 
  typical 
  tooth 
  of 
  this 
  species, 
  as 
  compared 
  with 
  the 
  T. 
  antiqua, 
  is 
  more 
  slender 
  and 
  curved. 
  In 
  a 
  length 
  of 
  

  

  crown 
  and 
  fang 
  slightly 
  exceeding 
  the 
  largest 
  of 
  the 
  latter, 
  the 
  diameters 
  are 
  all 
  about 
  one-half 
  the 
  same. 
  Teeth 
  

  

  from 
  other 
  portions 
  of 
  the 
  jaw 
  are 
  but 
  litle 
  stouter. 
  

  

  In. 
  Lin. 
  

  

  Length 
  of 
  tooth 
  from 
  New 
  Jersey, 
  (on 
  curve, 
  ) 
  3 
  8. 
  

  

  Diameter 
  at 
  base 
  crown, 
  6.6 
  

  

  Length 
  of 
  Maryland 
  specimen 
  16.5 
  lines. 
  Base 
  of 
  crown, 
  9 
  lines. 
  

   Miocene 
  of 
  New 
  Jersey 
  and 
  Maryland. 
  

  

  THECACHAMPSA 
  SQUANKENSIS, 
  Marsh. 
  

  

  Sillim. 
  Amer. 
  Journ. 
  Sci.Arts, 
  1869, 
  p. 
  391. 
  

  

  The 
  enamel 
  of 
  the 
  crowns 
  of 
  the 
  teeth, 
  is 
  in 
  this 
  species 
  quite 
  rugose. 
  The 
  cutting 
  edges 
  are 
  short, 
  and 
  promi- 
  

   nent 
  ; 
  the 
  general 
  form 
  cylindric 
  and 
  but 
  little 
  curved. 
  

  

  Miocene 
  of 
  Squankum, 
  Monmouth 
  Co., 
  N. 
  J. 
  Mus. 
  0. 
  C. 
  Marsh. 
  

  

  THECACHAMPSA 
  FASTIGIATA, 
  Leidy. 
  

  

  Crocodilus 
  fastiyiatus, 
  Leidy. 
  Proc. 
  A. 
  N. 
  S., 
  Phil., 
  1851, 
  327. 
  

   From 
  Eocene 
  of 
  Eastern 
  Virginia. 
  

  

  BOTTOSAURUS, 
  Agassiz. 
  

  

  The 
  characters 
  of 
  this 
  genus 
  have 
  never 
  been 
  pointed 
  out 
  to 
  the 
  knowledge 
  of 
  the 
  

   writer. 
  In 
  the 
  general 
  form 
  of 
  the 
  under 
  jaw 
  and 
  teeth 
  it 
  does 
  not 
  seem 
  to 
  differ 
  from 
  

   Alligator. 
  One 
  character 
  which 
  separates 
  it 
  from 
  that 
  genus 
  appears 
  to 
  be 
  similar 
  to 
  

   that 
  which 
  distinguishes 
  Thoracosaurus 
  from 
  Gavialis, 
  i. 
  e., 
  the 
  absence 
  of 
  long 
  simple 
  

   hypapophyses 
  on 
  the 
  cervical 
  vertebrae, 
  and 
  their 
  substitution 
  by 
  low 
  transverse 
  or 
  divided 
  

   elevations. 
  It 
  also 
  appears 
  that 
  the 
  great 
  external 
  foramen 
  which 
  separates 
  the 
  angular, 
  

   dentary 
  and 
  articular 
  bones 
  was 
  closed 
  up. 
  

  

  • 
  BOTTOSAURUS 
  HARLANI, 
  Meyer. 
  

  

  Crocodilus 
  harlani, 
  Meyer 
  Palaeologica, 
  1832, 
  108. 
  Crocodilus 
  macrorliynchus, 
  Harlan. 
  Jour. 
  Ac. 
  N. 
  Sci., 
  Phil., 
  

   1824, 
  15 
  (name 
  pre-occupied). 
  Bottosaurus 
  harlani, 
  Agassiz. 
  Leidy, 
  Cretaceous 
  Rept. 
  N. 
  Am., 
  12-14, 
  Tab. 
  

  

  The 
  teeth 
  of 
  this 
  species 
  are 
  similar 
  to 
  those 
  of 
  Alligator 
  in 
  the 
  short 
  obtuse 
  crowns. 
  The 
  pulp 
  cavity 
  is 
  remark- 
  

   ably 
  large 
  and 
  extends 
  into 
  the 
  crown, 
  leaving 
  the 
  dentine 
  and 
  enamel 
  at 
  the 
  apex 
  little 
  thicker 
  than 
  the 
  sides. 
  

  

  Besides 
  the 
  remains 
  described 
  by 
  Leidy, 
  portions 
  of 
  a 
  smaller, 
  perhaps 
  younger, 
  individual 
  have 
  been 
  presented 
  to 
  

   the 
  Academy 
  of 
  Natural 
  Sciences 
  by 
  Dr. 
  Ashhurst, 
  from 
  near 
  Birmingham, 
  N. 
  J. 
  They 
  consist 
  of 
  various 
  fragments 
  

   of 
  cranium 
  with 
  dermal 
  plates. 
  A 
  tooth 
  is 
  compressed, 
  but 
  has 
  a 
  short 
  conic 
  acute 
  crown, 
  such 
  as 
  has 
  not 
  before 
  

   been 
  seen 
  in 
  this 
  species. 
  

  

  The 
  interorbital 
  region 
  is 
  strongly 
  pitted 
  medially, 
  and 
  exhibits 
  on 
  each 
  side 
  a 
  deep, 
  short 
  groove. 
  There 
  are 
  no 
  

  

  marked 
  crests. 
  

  

  AMERI. 
  PHILOSO. 
  SOO. 
  — 
  VOL. 
  XIV. 
  It 
  

  

  