﻿1864.] 
  HUXLEY 
  ZIPHIUS. 
  395 
  

  

  Order 
  CETACEA. 
  

  

  Fam. 
  Rhynchoceti 
  (Eschricht). 
  

  

  Hyperobdontina 
  (Gray), 
  Ziphioidea 
  (Gervais). 
  

  

  Heterodontes 
  (Duvemoy). 
  

  

  Species. 
  Genera. 
  

  

  Recent 
  : 
  — 
  

  

  Hyperoodon 
  rostratum 
  Hyperoodon 
  (Lac6pede). 
  

  

  Berardius 
  Arnuxi 
  Berardius 
  (Duvernoy). 
  

  

  -r. 
  7 
  , 
  . 
  , 
  ( 
  Micropteron 
  (Eschricht). 
  

  

  Delphinus 
  micropterus 
  ) 
  M 
  lodon 
  ( 
  £ 
  ervais) 
  . 
  

  

  Delphinus 
  Sowerbtenszs 
  ] 
  Mesodiodon 
  (Duvernoy). 
  

  

  Delphinus 
  densirostris 
  ) 
  JDioplodon 
  (Gervais). 
  

  

  Dioplodon 
  Europceus 
  j 
  | 
  Mesodiodon 
  (Duvernoy). 
  

  

  The 
  Cetacean 
  of 
  Aresquiers 
  .... 
  ? 
  Ziphius 
  (Gervais). 
  

  

  Fossil 
  : 
  — 
  

  

  ? 
  Ziphius 
  cavirostris 
  Ziphius 
  (Cuvier). 
  

  

  Crag 
  :— 
  

  

  Ziphius 
  planirostris 
  Choneziphius 
  (Duvernoy). 
  

  

  Ziphius 
  longirostris 
  , 
  

  

  Ziphius 
  Becanii 
  

  

  Belemnoziphius 
  cornpressus 
  

  

  Ziphius 
  angustus 
  

  

  Ziphius 
  gibbus 
  

  

  Ziphius 
  declivus 
  

  

  Ziphius 
  angulatus 
  

  

  Ziphius 
  planus 
  

  

  Ziphius 
  undatus 
  

  

  1. 
  Unless 
  the 
  Cetacean 
  of 
  Aresquiers 
  be 
  identical 
  with 
  Ziphius 
  

   cavirostris, 
  all 
  the 
  Ziphii 
  of 
  Cuvier 
  belong 
  to 
  Cetacea 
  generically 
  

   distinct 
  from 
  those 
  now 
  living. 
  

  

  2. 
  If 
  the 
  Cetacean 
  of 
  Aresquiers 
  be 
  identical 
  with 
  Ziphius 
  cavi- 
  

   rostris, 
  it 
  is 
  not 
  certain 
  that 
  the 
  latter 
  is 
  truly 
  fossil 
  ; 
  nor, 
  if 
  it 
  be 
  

   so, 
  have 
  we 
  any 
  knowledge 
  of 
  its 
  stratigraphical 
  position. 
  

  

  3. 
  Of 
  the 
  certainly 
  fossil 
  Ziphii, 
  the 
  stratigraphical 
  position 
  of 
  

   Belemnoziphius 
  longirostris 
  is 
  unknown 
  ; 
  but 
  all 
  the 
  other 
  species 
  of 
  

   that 
  genus 
  and 
  Choneziphius 
  planirostris 
  are 
  derived 
  from 
  the 
  En- 
  

   glish 
  or 
  Antwerp 
  Crag, 
  and 
  are 
  not 
  known 
  to 
  occur 
  out 
  of 
  it. 
  

  

  4. 
  So 
  that 
  at 
  present 
  we 
  are 
  justified 
  in 
  regarding 
  Belemnoziphius 
  

   and 
  Choneziphius 
  as 
  true 
  Crag 
  mammals. 
  

  

  m 
  

  

  % 
  

  

  i 
  

  

  o 
  

  

  o 
  

  

  - 
  

  

  >Belemnoziphius 
  (Huxley). 
  

  

  J 
  

  

  Since 
  the 
  preceding 
  pages 
  were 
  in 
  type, 
  Professor 
  Yan 
  Beneden 
  has 
  

   had 
  the 
  goodness 
  to 
  send 
  me 
  his 
  interesting 
  and 
  valuable 
  memoirs, 
  

   " 
  Sur 
  une 
  nouvelle 
  Espece 
  de 
  Ziphius 
  " 
  and 
  " 
  On 
  Mesoplodon 
  Sower- 
  

   biensis,^ 
  published 
  in 
  the 
  ' 
  Bulletin' 
  of 
  the 
  Belgian 
  Academy 
  for 
  1863, 
  

   which 
  had 
  not 
  reached 
  me 
  at 
  the 
  time 
  these 
  pages 
  were 
  written. 
  

  

  The 
  new 
  " 
  Ziphius 
  indicus 
  " 
  appears 
  to 
  be 
  very 
  closely 
  allied 
  to 
  

   the 
  Cetacean 
  of 
  Aresquiers, 
  which 
  Professor 
  Yan 
  Beneden 
  agrees 
  with 
  

   M. 
  Gervais 
  in 
  identifying 
  with 
  Cuvier's 
  Z. 
  cavirostris. 
  In 
  the 
  course 
  

   of 
  his 
  memoir 
  on 
  this 
  species, 
  Professor 
  Yan 
  Beneden 
  refers 
  inciden- 
  

   tally 
  to 
  two 
  other 
  Ziphioid 
  Cetaceans 
  of 
  new 
  generic 
  types 
  — 
  " 
  Ziphi- 
  

   rostre 
  " 
  and 
  " 
  Placocete 
  " 
  ; 
  the 
  former 
  of 
  which 
  had 
  already 
  been 
  men- 
  

  

  