﻿76 
  PALEONTOLOGY 
  .OFJLLINOl 
  

  

  Belgium, 
  in 
  the 
  De 
  Koninck 
  collection, 
  belonging 
  to 
  the 
  Museum 
  of 
  

   Comparative 
  Zoology, 
  at 
  Cambridge, 
  bears 
  the 
  manuscript 
  nam 
  

   Taniadus 
  contortus, 
  de 
  Kon? 
  The 
  characteristics 
  which 
  distinguish 
  

   this 
  specimen 
  are 
  intimately 
  reproduced 
  in 
  the 
  American 
  /amples 
  f% 
  

   hereinafter 
  particularly 
  noticed, 
  and 
  which 
  constitute 
  a 
  well-defined 
  ' 
  

  

  form, 
  for 
  which 
  we 
  have 
  adopted 
  the 
  unpublished 
  appellation 
  1 
  

   stowed 
  upon 
  the 
  typical 
  species 
  recognized 
  by 
  Dr. 
  de 
  Koninck. 
  The 
  

   relations 
  of 
  these 
  teeth 
  are 
  apparently 
  near 
  Psephodut, 
  from 
  the 
  

   supposed 
  maxillary 
  median 
  forms 
  of 
  which 
  they 
  are 
  indeed 
  chiefly 
  

   distinguishable 
  by 
  the 
  pronounced 
  differentiation 
  of 
  the 
  coronal 
  con- 
  

   tour, 
  in 
  which 
  respect 
  they 
  approach 
  nearer 
  certain 
  remote 
  forms 
  

   of 
  typical 
  Cochliodonts, 
  e. 
  g., 
  Stenopterodus. 
  

  

  The 
  American 
  species 
  are 
  readily 
  distinguishable 
  from 
  the 
  con- 
  

   generic 
  Belgian 
  species, 
  T. 
  contortus, 
  de 
  Kon. 
  The 
  latter 
  is 
  remark- 
  

   able 
  for 
  its 
  comparatively 
  strong 
  inrollment, 
  Blightly 
  depressed 
  

   posterior 
  coronal 
  slope; 
  in 
  general 
  proportions 
  and 
  outlines 
  it 
  bears 
  

   closest 
  re3emllance 
  to 
  the 
  Chester 
  teeth, 
  T. 
  obUquvs. 
  

  

  The 
  genus 
  is 
  known 
  only 
  from 
  Carboniferous 
  strata, 
  of 
  which, 
  

   bi 
  sides 
  the 
  typical 
  European 
  representative, 
  there 
  are 
  authentic 
  de- 
  

   terminations 
  of 
  three 
  species 
  from 
  America, 
  all 
  from 
  the 
  Low 
  

   Carboniferous 
  series. 
  

  

  Tjeniodus 
  facia-its'.' 
  (N. 
  and 
  \Y. 
  sp.) 
  s/ 
  

  

  pl 
  xm, 
  riff. 
  9. 
  

  

  idtu 
  fat 
  iotua, 
  Newberry 
  and 
  Worthen, 
  1870, 
  I 
  8unr„ 
  iv. 
  p. 
  MS, 
  PL 
  III. 
  f. 
  17. 
  «f^ 
  

  

  Maxillary 
  posterior 
  tooth 
  attaining 
  large 
  size, 
  elongate 
  Bubtfrhom- 
  

   boidal 
  in 
  outline, 
  gently 
  arched 
  in 
  the 
  direction 
  of 
  inrollment. 
  

  

  Antero-lateral 
  border 
  relatively 
  short, 
  obliquely 
  produced 
  outward 
  

   and 
  forward 
  at 
  an 
  angle 
  of 
  about 
  '->."> 
  with 
  a 
  line 
  connecting 
  the 
  

  

  inner 
  angles 
  of 
  the 
  tooth; 
  postero-lateral 
  border 
  very 
  gradually 
  

  

  converging 
  toward 
  point 
  'of 
  inrollment 
  witli 
  a 
  gently 
  arched 
  OOUT84 
  

   — 
  character 
  of 
  coronal 
  fold 
  and 
  basal 
  rim 
  not 
  Known 
  in 
  fit 
  1 
  

  

  border; 
  inner 
  margin 
  making 
  nearly 
  a 
  right 
  angle 
  with 
  the 
  postero- 
  

   lateral 
  border 
  to 
  a 
  point 
  about 
  midway, 
  when 
  it 
  is 
  abruptly 
  

   rounded 
  and 
  deflected 
  forward 
  with 
  a 
  Blightly 
  concave 
  oourat 
  then 
  

  

  to 
  the 
  obtuse 
  anterior 
  angle, 
  worn 
  specimen'' 
  beveled 
  interiorly. 
  

  

  Crown 
  surface 
  ohiefly 
  oooapied 
  by 
  the 
  posterior 
  prominence, 
  whiofa 
  

  

  pn 
  -.Mi- 
  :i 
  broad 
  gently 
  oonvei 
  dope 
  rising 
  from 
  the 
  | 
  lateral 
  

  

  boarder 
  into 
  the 
  orest, 
  the 
  opposite 
  Bide 
  more 
  abruptly 
  desoend- 
  

  

  and 
  merging 
  into 
  the 
  shallow 
  depression 
  oooapying 
  the 
  anterior 
  

  

  portion 
  of 
  the 
  crown; 
  ihe 
  surfaci 
  is 
  nn 
  re 
  or 
  ly 
  marked 
  

  

  