﻿VEETEBEATES. 
  

  

  203 
  

  

  The 
  teeth 
  are 
  so 
  variable 
  in 
  relative 
  dimensions 
  that 
  comparative 
  

   measurements 
  are 
  of 
  little 
  use 
  for 
  other 
  purpose 
  than 
  to 
  show 
  the 
  

   maxima 
  attained 
  by 
  the 
  species, 
  as 
  indicated 
  by 
  the 
  breadth; 
  thus, 
  

   the 
  largest 
  perfect 
  example 
  shows 
  a 
  transverse 
  diameter 
  across 
  the 
  

   posterior 
  margin 
  of 
  33 
  mm., 
  the 
  smallest 
  perfect 
  tooth 
  measuring 
  

   about 
  16 
  mm. 
  in 
  breadth. 
  

  

  A 
  form 
  differing 
  from 
  that 
  above 
  

   noticed 
  chiefly 
  in 
  the 
  proportion- 
  

   ately 
  greater 
  length 
  of 
  the 
  teeth, 
  

   compared 
  to 
  their 
  breadth, 
  giving 
  

   them 
  a 
  more 
  lozenge-shaped 
  outline 
  

   are 
  quite 
  as 
  numerously 
  represented 
  

   in 
  the 
  collections, 
  and 
  which 
  we 
  sup- 
  

   pose 
  to 
  have 
  constituted 
  the 
  arm- 
  

   ature 
  of 
  the 
  opposite 
  jaw 
  of 
  the 
  

   same 
  species. 
  Examples 
  of 
  much- 
  

   worn, 
  mature 
  teeth 
  present 
  an 
  

   almost 
  regular 
  arch, 
  or 
  curvature, 
  

   from 
  the 
  inner 
  anterior 
  to 
  the 
  outer 
  

   posterior 
  spur 
  angle 
  without 
  dis- 
  

   tinct 
  intermediate 
  angulation 
  at 
  the 
  

   junction 
  of 
  the 
  exterior 
  border 
  with 
  

   the 
  anterior 
  margin, 
  and 
  the 
  inner 
  

   coronal 
  prominence, 
  as 
  also 
  the 
  

   outer 
  lesser 
  ridge, 
  is 
  reduced 
  to 
  a 
  

   nearly 
  plane 
  surface 
  transversely. 
  

   The 
  inner 
  articular 
  border 
  is 
  quite 
  

   straight, 
  extremely 
  thickened 
  and 
  

   wedging 
  out 
  towards 
  the 
  exterior 
  

   border; 
  in 
  every 
  instance 
  of 
  the 
  teeth 
  here 
  admitted, 
  the 
  truncated 
  

   facet 
  is 
  extremely 
  small, 
  sometimes 
  occurring 
  at 
  one 
  angle, 
  again 
  at 
  

   the 
  opposite 
  ; 
  however, 
  most 
  of 
  the 
  specimens 
  being 
  truncated 
  at 
  the 
  

   posterior 
  angle. 
  The 
  very 
  gentle 
  longitudinal 
  convexity 
  of 
  the 
  coronal 
  

   surface 
  of 
  the 
  tooth 
  indicate 
  that 
  the 
  curvature 
  of 
  the 
  series 
  constituted 
  

   a 
  smaller 
  segment 
  of 
  a 
  circle 
  than 
  was 
  the 
  case 
  with 
  the 
  before- 
  

   mentioned 
  form; 
  hence 
  the 
  supposition 
  of 
  their 
  maxillary 
  position. 
  

   In 
  dimensions, 
  as 
  also 
  in 
  surface 
  structure, 
  the 
  form 
  agrees 
  with 
  

   that 
  previously 
  noticed. 
  

  

  Diagram 
  of 
  maxillary 
  teeth 
  of 
  Paammo- 
  

   dus 
  ISprinqeri. 
  

  

  Maxillary 
  series, 
  triturating 
  surface. 
  

   Transverse 
  profile 
  of 
  maxillary 
  se- 
  

  

  h. 
  

   ries, 
  

  

  c. 
  Longitudinal 
  profiles 
  of 
  maxillary 
  

   series. 
  

  

  