﻿Classification 
  of 
  the 
  Order 
  Iniomi. 
  129 
  

  

  mesethmoid, 
  so 
  that 
  the 
  lateral 
  ethmoids 
  are 
  separated 
  and 
  

   are 
  almost 
  entirely 
  below 
  the 
  level 
  of 
  the 
  parasphenoid 
  ; 
  the 
  

   mesethmoid 
  bears 
  a 
  prominent 
  median 
  ridge. 
  The 
  jaws, 
  the 
  

   palatine 
  attachment, 
  and 
  the 
  post-temporals 
  are 
  as 
  in 
  Chloro- 
  

   phthalmus 
  ; 
  the 
  mesopterygoid 
  is 
  well-developed, 
  but 
  does 
  

   not 
  overlap 
  the 
  parasphenoid 
  ; 
  the 
  suboperculum 
  and 
  branchio- 
  

   stegals 
  are 
  not 
  curved 
  upwards 
  behind 
  the 
  operculum 
  ; 
  except 
  

   for 
  the 
  post-temporal 
  attachment 
  the 
  pectoral 
  arch 
  is 
  very 
  

   much 
  as 
  in 
  Aidopus; 
  the 
  pelvic 
  bones 
  are 
  small 
  triangular 
  

   plates. 
  

  

  There 
  are 
  32 
  vertebrae 
  ; 
  there 
  are 
  12 
  pairs 
  of 
  ribs, 
  the 
  last 
  

   7 
  inserted 
  on 
  parapophyses 
  which 
  increase 
  in 
  length 
  back- 
  

   wards 
  ; 
  series 
  of 
  epineurals 
  and 
  epipleurals 
  are 
  present 
  ; 
  there 
  

   are 
  3 
  epurals 
  and 
  2 
  uroneurals 
  and 
  the 
  last 
  centrum 
  is 
  up- 
  

   turned. 
  

  

  Lampanyctus 
  is 
  a 
  much 
  more 
  specialized 
  form, 
  with 
  slender 
  

   adherent 
  maxillary 
  and 
  oblique 
  suspensorium 
  ; 
  the 
  skull 
  is 
  

   as 
  broad 
  as 
  long, 
  but 
  agrees 
  with 
  that 
  of 
  JS'eoscopelus 
  in 
  

   essentials. 
  The 
  vertebral 
  column 
  has 
  35 
  vertebrae 
  ; 
  all 
  the 
  

   ribs 
  are 
  inserted 
  on 
  parapophyses. 
  

  

  Suborder 
  2. 
  Alepidosaukoidea. 
  

  

  Head 
  and 
  body 
  compressed 
  ; 
  caudal 
  well 
  developed, 
  free 
  

   from 
  the 
  anal 
  ; 
  pectorals 
  low 
  ; 
  pelvics 
  6-13 
  rayed, 
  close 
  

   together, 
  far 
  behind 
  the 
  pectorals. 
  Mouth 
  large, 
  not 
  pro- 
  

   tractile; 
  strong 
  pointed 
  canines 
  in 
  the 
  lower 
  jaw 
  and 
  on 
  the 
  

   palatines 
  ; 
  prtemaxillary 
  and 
  maxillary 
  long 
  and 
  slender, 
  

   firmly 
  united 
  distally. 
  Palatine 
  large, 
  vertically 
  expanded 
  

   anteriorly, 
  where 
  it 
  is 
  firmly 
  attached 
  by 
  its 
  upper 
  edge 
  to 
  

   the 
  frontal 
  and 
  by 
  its 
  inner 
  face 
  to 
  the 
  side 
  of 
  the 
  ethmoidal 
  

   region 
  ; 
  mesopterygoid 
  rather 
  small. 
  Pneoperculum 
  narrow, 
  

   nearly 
  vertical 
  ; 
  suboperculum 
  entirely 
  below 
  operculum 
  ; 
  

   interoperculum 
  reduced 
  ; 
  6 
  to 
  8 
  branchiostegals. 
  Ethmoid 
  

   without 
  median 
  keel 
  or 
  lateral 
  processes 
  ; 
  parasphenoid 
  

   slehider 
  ; 
  a 
  basisphenoid 
  ; 
  no 
  orbitosphenoid. 
  Upper 
  fork 
  of 
  

   post-temporal 
  connected 
  by 
  ligament 
  with 
  epiotic, 
  but 
  nearly 
  

   meeting 
  its 
  fellow 
  above 
  the 
  supraoccipital 
  ; 
  cleithium 
  at- 
  

   tached 
  to 
  supracleithrum 
  near 
  upper 
  end 
  of 
  the 
  latter, 
  which 
  

   runs 
  obliquely 
  downwards 
  and 
  backwards 
  and 
  has 
  the 
  upper 
  

   postcleithrum 
  attached 
  to 
  its 
  distal 
  end. 
  Pelvic 
  bones 
  

   simple 
  rods 
  or 
  triangular 
  plates. 
  No 
  upturned 
  centra 
  at 
  the 
  

   base 
  of 
  the 
  caudal 
  fin. 
  No 
  air-bladder. 
  

  

  This 
  suborder 
  contains 
  a 
  few 
  deep-sea 
  fishes 
  with 
  the 
  

   skeleton 
  rather 
  weakly 
  ossified. 
  

  

  Ann. 
  & 
  Mag. 
  N. 
  Hist. 
  Ser. 
  8. 
  Vol. 
  vii. 
  9 
  

  

  