﻿120 
  Mr. 
  0. 
  T. 
  Regan 
  on 
  the 
  Anatomy 
  and 
  

  

  XIII. 
  — 
  The 
  Anatomy 
  and 
  Classification 
  of 
  the 
  Teleostean 
  

   Fishes 
  of 
  the 
  Order 
  Iniomi. 
  By 
  C. 
  Tate 
  ReGAN, 
  M. 
  A. 
  

  

  (Published 
  by 
  permission 
  of 
  the 
  Trustees 
  of 
  the 
  British 
  Museum.) 
  

  

  The 
  Iniomi 
  are 
  marine 
  malacopterous 
  physostomes 
  with 
  the 
  

   pelvic 
  fins 
  abdominal 
  or 
  thoracic 
  in 
  position 
  and 
  the 
  pelvic 
  

   bones 
  free 
  from 
  the 
  cleithra 
  ; 
  an 
  adipose 
  dorsal 
  fin 
  is 
  typically 
  

   present, 
  the 
  prsemaxillaries 
  exclude 
  the 
  maxillaries 
  from 
  the 
  

   gape, 
  the 
  gill-openings 
  are 
  wide, 
  the 
  pectoral 
  arch 
  is 
  attached 
  

   to 
  the 
  skull 
  by 
  a 
  forked 
  post-temporal, 
  there 
  is 
  no 
  meso- 
  

   coracoid, 
  the 
  vertebral 
  centra 
  are 
  coossified 
  with 
  the 
  arches, 
  

   the 
  air-bladder 
  is 
  small 
  or 
  absent, 
  and 
  the 
  ovaries 
  are 
  pro- 
  

   vided 
  with 
  oviducts. 
  

  

  The 
  families 
  Rondeletiidse 
  and 
  Cetomimidee 
  are 
  known 
  

   only 
  from 
  a 
  few 
  specimens 
  taken 
  in 
  deep 
  water; 
  they 
  pre- 
  

   sumably 
  pertain 
  to 
  this 
  order, 
  for 
  the 
  prsemaxillaries 
  form 
  

   the 
  upper 
  border 
  of 
  the 
  mouth, 
  but 
  these 
  fishes 
  differ 
  from 
  the 
  

   rest 
  in 
  the 
  posterior 
  position 
  of 
  the 
  dorsal 
  fin, 
  which 
  is 
  

   opposed 
  to 
  the 
  anal. 
  They 
  will 
  probably 
  form 
  a 
  distinct 
  

   suborder 
  when 
  they 
  are 
  better 
  known. 
  

  

  Of 
  the 
  Cretaceous 
  fishes 
  which 
  may 
  pertain 
  to 
  the 
  Iniomi 
  

   the 
  Chirothricidse 
  are 
  probably 
  related 
  to 
  the 
  AulopidEe 
  or 
  

   Sudidee, 
  but 
  the 
  Enchodontidse 
  appear 
  to 
  me 
  to 
  show 
  more 
  

   agreement 
  with 
  the 
  Stomiatidse 
  than 
  with 
  the 
  Alepidosauroids, 
  

   to 
  which 
  Smith 
  Woodward 
  considers 
  they 
  are 
  related. 
  The 
  

   Dercetida? 
  are 
  of 
  uncertain 
  relationships, 
  but 
  the 
  orbital 
  and 
  

   postorbital 
  parts 
  of 
  the 
  skull 
  and 
  the 
  post-temporals 
  show 
  

   considerable 
  resemblance 
  to 
  Evermanella 
  (Odontostomus), 
  

   whilst 
  the 
  ethmoid 
  region 
  and 
  jaws 
  are 
  more 
  like 
  those 
  of 
  

   Alepidosaurus. 
  Of 
  the 
  fishes 
  placed 
  by 
  Smith 
  Woodward 
  

   in 
  the 
  Scopelidss 
  many 
  are 
  of 
  very 
  doubtful 
  position, 
  but 
  

   Sardinioides 
  crassicauda 
  and 
  illustrans 
  certainly 
  belong 
  to 
  

   the 
  Aulopida?. 
  Other 
  species 
  referred 
  to 
  Sardinioides 
  re- 
  

   semble 
  Neoscopelus 
  or 
  Ch/orophthalmus, 
  to 
  which 
  Acrognathus 
  

   may 
  be 
  related. 
  Apateodus 
  is 
  probably 
  near 
  Alepidosaurus. 
  

  

  The 
  skeletal 
  characters 
  of 
  the 
  Iniomi 
  have 
  not 
  hitherto 
  

   received 
  much 
  attention. 
  Giinther 
  has 
  figured 
  the 
  pectoral 
  

   arch 
  of 
  Omosudis 
  and 
  Bathypterois 
  (' 
  Challenger 
  ' 
  Deep-sea 
  

   Fishes). 
  Gill 
  has 
  pointed 
  out 
  that 
  in 
  several 
  families 
  the 
  

   post-temporals 
  " 
  impinge 
  upon 
  the 
  occiput." 
  Smith 
  Wood- 
  

   ward 
  has 
  figured 
  the 
  head 
  skeleton 
  of 
  Aulopus 
  for 
  comparison 
  

   with 
  Sardinioides 
  (Palceontograph. 
  Soc. 
  1902). 
  

  

  