﻿VEETEBEATES. 
  121 
  

  

  defined 
  by 
  a 
  narrow 
  channel 
  from 
  the 
  downward 
  and 
  outward 
  pro- 
  

   jecting 
  basal 
  portion, 
  which 
  terminates 
  in 
  a 
  thin 
  rim 
  inferiorly, 
  the 
  

   axes 
  of 
  the 
  channel 
  showing 
  relatively 
  coarse 
  pits 
  ; 
  postero-lateral 
  

   border 
  with 
  a 
  moderate 
  sigmoidal 
  curvature, 
  diverging 
  posteriorly 
  

   at 
  an 
  angle 
  of 
  50° 
  with 
  the 
  opposite 
  border^ 
  terminated' 
  in 
  the 
  i 
  n 
  .f 
  

   acutely 
  rounded 
  posterior 
  angle, 
  coronal 
  fold 
  equally 
  sharply 
  de- 
  

   fined 
  from 
  the 
  basal 
  portion, 
  which 
  is 
  more 
  or 
  less 
  expanded 
  

   toward 
  the 
  posterior 
  extremity 
  where 
  it 
  forms 
  a 
  wide 
  platform 
  

   extending 
  beyond 
  the 
  limits 
  of 
  the 
  coronal 
  border, 
  the 
  channel 
  

   similarly 
  marked 
  by 
  a 
  row 
  of 
  large 
  vascular 
  pits; 
  general 
  direction 
  

   of 
  inner 
  margin 
  nearly 
  at 
  right 
  angles 
  to 
  the 
  antero-lateral 
  border, 
  

   broadly 
  arched 
  round 
  the 
  base 
  of 
  the 
  median 
  prominence, 
  and 
  

   again 
  gently 
  curved 
  sigmoidally 
  in 
  passing 
  to 
  the 
  posterior 
  ex- 
  

   tremity/ 
  coronal 
  region 
  defined 
  by 
  an 
  abruptly 
  inbeveled 
  narrow 
  

   fold 
  from 
  the 
  deep 
  basal 
  area 
  which 
  terminates 
  inferiorly 
  in 
  a 
  very 
  

   thin 
  edge/ 
  surface 
  irregularly 
  and 
  coarsely 
  marked 
  by 
  vertical 
  

   rugosities 
  and 
  sulci/— 
  usually, 
  however, 
  the 
  attenuated 
  rim 
  is 
  

   broken 
  away, 
  and 
  the 
  margin 
  abruptly 
  inbeveled. 
  Coronal 
  contour 
  

   strongly 
  arched 
  in 
  the 
  direction 
  of 
  inrollment 
  ; 
  anterior 
  belt 
  well 
  

   defined 
  from 
  the 
  median 
  prominence, 
  slightly, 
  sometimes 
  strongly, 
  

   arched 
  transversely, 
  with 
  a 
  slight 
  furrow 
  along 
  the 
  anterior 
  edge 
  in 
  

   well 
  preserved 
  examples 
  ; 
  median 
  prominence 
  occupying 
  half 
  the 
  lateral 
  

   diameter 
  of 
  the 
  crown, 
  strongly 
  and 
  regularly 
  arched 
  transversely, 
  

   the 
  rounded 
  axis 
  lying 
  a 
  little 
  anterior 
  of 
  the 
  middle, 
  the 
  broader 
  

   slope 
  descending 
  into 
  the 
  posterior 
  depression 
  where 
  it 
  is 
  defined 
  

   by 
  a 
  marked 
  angulation 
  ; 
  posterior 
  alation 
  proportionately 
  wider 
  

   than 
  the 
  anterior 
  plane 
  belt, 
  faintly 
  depressed 
  in 
  the 
  middle 
  and 
  

   slightly 
  arched 
  transversely 
  along 
  the 
  moderately 
  upraised 
  postero- 
  

   lateral 
  border, 
  where 
  the 
  edge 
  of 
  the 
  coronal 
  enamel 
  is 
  inbeveled 
  

   similarly 
  to 
  the 
  enamel 
  fold 
  along 
  the 
  antero-lateral 
  border, 
  and 
  

   rounded 
  at 
  the 
  extremity. 
  Along 
  the 
  inner 
  margin 
  of 
  the 
  well 
  pre- 
  

   served 
  tooth 
  the 
  surface 
  is 
  invested 
  in 
  a 
  dense 
  semi-opaque 
  enamel 
  

   through 
  which 
  the 
  extremities 
  of 
  the 
  tubular 
  structure 
  are 
  faintly 
  

   outlined; 
  in 
  worn 
  surfaces, 
  this 
  same 
  structure 
  produces 
  a 
  minute, 
  

   rather 
  widely 
  spaced 
  punctuation, 
  of 
  which 
  there 
  are 
  about 
  30 
  

   pores 
  in 
  the 
  space 
  of 
  a 
  square 
  millimetre. 
  Greatest 
  transverse 
  

   diameter 
  of 
  the 
  crown 
  of 
  a 
  medium-size 
  example 
  across 
  the 
  inner 
  

   margin 
  15 
  mm., 
  or 
  to 
  the 
  extremity 
  of 
  the 
  basal 
  spur 
  17 
  mm.; 
  

   length 
  of 
  antero-lateral 
  border 
  to 
  point 
  of 
  inrollment 
  10 
  mm.; 
  

   greatest 
  depth 
  ditto, 
  1.5 
  mm. 
  ; 
  length 
  along 
  postero-lateral 
  border 
  

   to 
  the 
  inrolled 
  outer 
  margin 
  10 
  mm. 
  

  

  