﻿1864.] 
  HUXLEY 
  ZIPHIUS. 
  391 
  

  

  bidens 
  ; 
  and 
  Professor 
  Eschricht, 
  it 
  will 
  be 
  observed, 
  substantially 
  

   agrees 
  with 
  him, 
  inasmuch 
  as 
  he 
  ranges 
  Sowerby's 
  Dolphin 
  in 
  Mi- 
  

   cropteron. 
  M. 
  Gervais, 
  in 
  his 
  " 
  Memoire 
  sur 
  la 
  Eamille 
  des 
  Cetaces 
  

   Ziphioides," 
  published 
  in 
  the 
  ' 
  Annales 
  des 
  Scierces 
  Natu 
  relies 
  ' 
  for 
  

   1850, 
  brought 
  forward 
  a 
  new 
  series 
  of 
  considerations, 
  tending 
  to 
  

   refer 
  Ziphius 
  to 
  a 
  recent 
  type; 
  and 
  as 
  M. 
  Gervais 
  entertains 
  the 
  

   conviction 
  that 
  no 
  living 
  species 
  of 
  mammal 
  existed 
  during 
  any 
  Ter- 
  

   tiary 
  epoch, 
  his 
  identification 
  of 
  Cuvier's 
  Ziphius 
  cavirostris 
  with 
  the 
  

   living 
  Mediterranean 
  species 
  of 
  Cetacean 
  stranded 
  at 
  Aresquiers, 
  in 
  

   the 
  Department 
  of 
  Herault, 
  in 
  May 
  1850, 
  led 
  him 
  to 
  dispute 
  the 
  

   truly 
  fossil 
  character 
  of 
  Ziphius 
  cavirostris. 
  M. 
  Gervais 
  justly 
  

   draws 
  attention 
  to 
  the 
  differences 
  between 
  Ziphius 
  cavirostris 
  and 
  the 
  

   two 
  other 
  Cuvierian 
  species, 
  and 
  indicates 
  what 
  he 
  conceives 
  to 
  be 
  

   the 
  close 
  analogy 
  of 
  Ziphius 
  longirostris 
  with 
  the 
  recent 
  Delphinus 
  

   densirostris, 
  which 
  he 
  ranges 
  in 
  a 
  distinct 
  genus, 
  under 
  the 
  name 
  of 
  

   Dioplodon. 
  

  

  At 
  the 
  same 
  time 
  he 
  establishes 
  the 
  genus 
  Mesoplodon 
  for 
  Sow- 
  

   erby's 
  Dolphin 
  ; 
  and 
  he 
  combines 
  all 
  these 
  genera, 
  namely, 
  Ziphius, 
  

   Dioplodon, 
  and 
  Mesoplodon, 
  with 
  Hyperoodon, 
  into 
  the 
  family 
  of 
  

   Getacea 
  Ziphioidea. 
  

  

  But, 
  as 
  M. 
  Gervais 
  agrees 
  with 
  Eschricht 
  in 
  identifying 
  Sowerby's 
  

   Dolphin 
  with 
  Delphinus 
  micropterus, 
  he 
  was 
  bound 
  to 
  adopt 
  Eschricht's 
  

   name, 
  Micropteron, 
  instead 
  of 
  inventing 
  a 
  new 
  one 
  {Mesoplodon) 
  to 
  

   cover 
  the 
  same 
  group 
  ; 
  and, 
  similarly, 
  " 
  Getacea 
  Ziphioidea 
  " 
  can 
  only 
  

   be 
  regarded 
  as 
  a 
  synonym 
  of 
  " 
  RhynchocetV 
  and 
  " 
  Hyper 
  oodontinaz" 
  

  

  In 
  the 
  ' 
  Annales 
  des 
  Sciences 
  ' 
  for 
  1851, 
  M, 
  Duvernoy 
  made 
  public 
  

   the 
  results 
  of 
  his 
  investigations 
  into 
  Cetacean 
  osteology, 
  in 
  an 
  essay, 
  

   accompanied 
  by 
  excellent 
  figures 
  *. 
  

  

  Refusing 
  to 
  admit 
  the 
  identity 
  of 
  the 
  Cetacean 
  of 
  Aresquiers 
  with 
  

   Ziphius 
  cavirostris 
  (Cuv.), 
  M. 
  Duvernoy 
  considers 
  it 
  to 
  be 
  a 
  Hyper- 
  

   oodon 
  of 
  a 
  new 
  species, 
  which 
  he 
  terms 
  H. 
  Gervaisii. 
  

  

  The 
  absence 
  of 
  the 
  maxillary 
  crest 
  characteristic 
  of 
  Hyperoodon, 
  

   and 
  the 
  difference 
  in 
  dentition 
  between 
  the 
  Cetacean 
  of 
  Aresquiers 
  

   and 
  that 
  genus, 
  however, 
  appear 
  to 
  me 
  to 
  be 
  fatal 
  obstacles 
  in 
  the 
  

   way 
  of 
  this 
  step. 
  Further, 
  M. 
  Duvernoy 
  substitutes 
  for 
  M. 
  Gervais's 
  

   two 
  genera 
  Dioplodon 
  and 
  Mesoplodon, 
  one, 
  Mesodiodon, 
  which 
  em- 
  

   braces 
  the 
  species 
  Delphinus 
  Sowerbiensis, 
  D. 
  micropterus 
  (regarded 
  as 
  

   a 
  distinct 
  species), 
  D. 
  densirostris, 
  and 
  the 
  fossil 
  Ziphius 
  longirostris. 
  

  

  But 
  Mesodiodon, 
  as 
  thus 
  composed, 
  is 
  clearly 
  only 
  a 
  synonym 
  of 
  

   Micropteron. 
  

  

  Ziphius 
  planirostris 
  is 
  made 
  the 
  type 
  of 
  a 
  new 
  genus, 
  Ghoneziphius, 
  

   distinguished 
  by 
  its 
  large 
  maxillary 
  fossae 
  and 
  by 
  the 
  union 
  of 
  the 
  

   premaxillee 
  on 
  the 
  upper 
  surface 
  of 
  the 
  snout. 
  Ziphius 
  cavirostris, 
  

   lastly, 
  is 
  retained 
  as 
  the 
  type 
  of 
  the 
  restricted 
  genus 
  Ziphius. 
  

  

  Thus 
  Cuvier's 
  three 
  species 
  of 
  Ziphius 
  are 
  referred 
  by 
  Duvernoy, 
  

   and 
  I 
  believe 
  rightly, 
  to 
  as 
  many 
  genera 
  ; 
  while 
  for 
  that 
  group 
  of 
  

   Cetacea 
  which 
  contains 
  these 
  genera, 
  Hyperoodon, 
  and 
  a 
  new 
  form, 
  

  

  * 
  " 
  Memoires 
  sur 
  les 
  Caracteres 
  osteologiques 
  des 
  Genres 
  nouveaux 
  ou 
  des 
  

   Especes 
  nouvelles 
  de 
  Cetaces 
  vivants 
  ou 
  fossiles," 
  ' 
  Annales 
  des 
  Sciences 
  Natu- 
  

   relles,' 
  ser. 
  iii. 
  torn, 
  xv, 
  

  

  