﻿Mr. 
  J. 
  W. 
  Gregory 
  on 
  Zeuglopleurus. 
  493 
  

  

  the 
  zone 
  a 
  Radiol 
  ites 
  and 
  a 
  var. 
  minor, 
  a 
  small 
  round 
  form, 
  

   from 
  the 
  zone 
  of 
  Epiaster 
  Heherti, 
  Coquand. 
  

  

  M. 
  Cotteau 
  had 
  shortly 
  before 
  this 
  published 
  his 
  principal 
  

   contributions 
  to 
  the 
  literature 
  of 
  Glyphocyphus 
  and 
  Echino- 
  

   cyphus'j 
  in 
  the 
  ' 
  Paleontologie 
  Francaise' 
  he 
  gave 
  elaborate 
  

   descriptions 
  and 
  figures 
  of 
  the 
  former 
  genus 
  in 
  1864 
  * 
  and 
  

   of 
  the 
  latter 
  in 
  I860 
  f. 
  He 
  then 
  incorporated 
  the 
  type 
  

   and 
  several 
  other 
  species 
  of 
  Hemidiadema, 
  Ag., 
  in 
  Glypho- 
  

   cyphus. 
  In 
  1865 
  he 
  redescribed 
  and 
  figured 
  J 
  the 
  con- 
  

   iexta 
  variety 
  of 
  Qlypliocyphus 
  radiatus. 
  

  

  Dr. 
  Wright, 
  in 
  1870 
  §, 
  was 
  the 
  next 
  palaeontologist 
  to 
  

   describe 
  and 
  figure 
  the 
  genera, 
  and 
  his 
  most 
  important 
  con- 
  

   tribution 
  to 
  our 
  knowledge 
  of 
  their 
  structure 
  was 
  that, 
  though 
  

   in 
  his 
  generic 
  diagnosis 
  of 
  Echinocyphus 
  he 
  described 
  the 
  

   apical 
  disk 
  as 
  unknown, 
  he 
  nevertheless 
  figured 
  and 
  described 
  

   that 
  of 
  E. 
  difficilis 
  [|. 
  

  

  The 
  Algerian 
  specimens 
  of 
  Glyphocyphus 
  radiatus 
  were 
  

   again 
  described 
  ^ 
  by 
  MM. 
  Cotteau, 
  Peron, 
  and 
  Gauthier 
  

   in 
  1879, 
  and 
  in 
  1879 
  Prof. 
  K. 
  von 
  Zittel 
  pithily 
  summarized 
  

   the 
  two 
  genera 
  **, 
  but 
  described 
  the 
  furrowed 
  sutures 
  of 
  

   Echinocyphus 
  as 
  limited 
  to 
  the 
  median 
  interambulacral 
  suture, 
  

   and 
  those 
  of 
  Glyphocyphus 
  as 
  affecting 
  also 
  the 
  horizontal 
  

   ones, 
  whereas 
  the 
  horizontal 
  sutures 
  of 
  Echinocyphus 
  are 
  more 
  

   markedly 
  furrowed 
  than 
  those 
  of 
  the 
  other 
  genus, 
  as 
  can 
  be 
  

   seen 
  in 
  Wright's 
  drawings 
  or 
  in 
  his 
  specimens. 
  Dr. 
  Schluter 
  

   in 
  1883 
  redescribed 
  E. 
  pusilla, 
  Roem., 
  and 
  included 
  it 
  in 
  

   Echinocyphus 
  ; 
  and 
  as 
  he 
  leaves 
  E. 
  pusilla, 
  Miinst.. 
  in 
  the 
  

   same 
  genus, 
  has 
  renamed 
  Rcemer's 
  species 
  Echinocyphus 
  

   pisum 
  • 
  as, 
  however, 
  this 
  belongs 
  to 
  Zeuglopleurus, 
  the 
  original 
  

   name 
  will 
  stand. 
  Finally 
  Pomel, 
  in 
  1883 
  ft, 
  has 
  insisted 
  

   that 
  in 
  Glyphocyphus 
  the 
  furrowing 
  of 
  the 
  sutures 
  is 
  limited 
  

   to 
  a 
  couple 
  of 
  fossettes 
  under 
  the 
  primary 
  tubercles 
  ; 
  this 
  is 
  

  

  * 
  Paleont. 
  Francaise, 
  Terr. 
  Cr6t. 
  t. 
  vii. 
  feuilles 
  34, 
  85 
  (1804), 
  pp. 
  531- 
  

   546, 
  pis. 
  1127, 
  1128. 
  

  

  t 
  Op. 
  at. 
  feuille 
  45 
  (1865), 
  pp. 
  707-716, 
  pis. 
  1174, 
  1175. 
  

  

  % 
  'Etudes 
  sur 
  les 
  Echinides 
  fossiles 
  du 
  departemeut 
  de 
  l'Yonne,' 
  

   feuille 
  16 
  (1865), 
  pp. 
  230-233. 
  

  

  § 
  ' 
  Monograph 
  of 
  the 
  British 
  Fossil 
  Echinodermata 
  from 
  the 
  Creta- 
  

   ceous 
  Formations,' 
  vol. 
  i. 
  pt. 
  3. 
  Palseontogr. 
  Soc. 
  1870 
  [1869], 
  pp. 
  116- 
  

   124, 
  pi. 
  xxii. 
  figs. 
  1-4, 
  pi. 
  xxix 
  B. 
  figs. 
  1, 
  2. 
  

  

  || 
  Loc. 
  cit. 
  pi. 
  xxii. 
  fig. 
  4. 
  

  

  *\ 
  ' 
  Echinides 
  fossiles 
  de 
  l'Algerie,' 
  t. 
  i. 
  fasc. 
  5 
  (Paris, 
  1879), 
  pp. 
  205- 
  

   207. 
  

  

  ** 
  < 
  Handbuch 
  der 
  Palseontologie,' 
  Bd. 
  i. 
  pp. 
  503, 
  506. 
  

  

  ft 
  ' 
  Classification 
  methodique 
  et 
  genera 
  des 
  Echinides 
  vivants 
  et 
  

   fossiles 
  ' 
  (Alger, 
  1883), 
  p. 
  103. 
  

  

  Ann. 
  & 
  Mag. 
  N. 
  Hist. 
  Ser. 
  6. 
  Vol. 
  iii. 
  34 
  

  

  