﻿328 
  Mr. 
  C. 
  T. 
  Regan 
  on 
  the 
  

  

  pelvic 
  iins 
  are 
  abdominal, 
  6-rayed. 
  The 
  scales 
  are 
  thin 
  and 
  

   cycloid, 
  and 
  the 
  lateral 
  line 
  runs 
  very 
  low. 
  The 
  prse- 
  

   maxillaries 
  are 
  non-protractile 
  and 
  the 
  maxillaries 
  enter 
  the 
  

   border 
  of 
  the 
  mouth 
  to 
  a 
  greater 
  or 
  less 
  extent 
  ; 
  the 
  lower 
  

   jaw 
  includes 
  a 
  sesamoid 
  articulare, 
  composed 
  of 
  a 
  laminar 
  

   portion 
  adherent 
  to 
  the 
  inuer 
  face 
  of 
  the 
  articulare, 
  and 
  of 
  a 
  

   rather 
  stout 
  process 
  which 
  projects 
  above 
  the 
  edge 
  of 
  the 
  

   jaw 
  ; 
  the 
  hyo-palatine 
  and 
  opercular 
  bones 
  are 
  normally 
  

   developed; 
  the 
  branchiostcgals 
  number 
  from 
  9 
  to 
  15; 
  the 
  

   more 
  or 
  less 
  enlarged 
  third 
  upper 
  pharyngeals 
  are 
  denti- 
  

   gerous, 
  opposed 
  to 
  the 
  united 
  lower 
  pharyngeals 
  ; 
  the 
  fourth 
  

   are 
  small 
  or 
  absent 
  ; 
  the 
  upper 
  surface 
  of 
  the 
  cranium 
  is 
  

   flatfish, 
  without 
  crests; 
  the 
  nasals 
  are 
  superior 
  in 
  position, 
  

   firmly 
  united 
  to 
  the 
  frontals 
  and 
  ethmoid 
  ; 
  the 
  upper 
  edge 
  

   of 
  the 
  large 
  prseorbital 
  is 
  attached 
  to 
  the 
  outer 
  edge 
  of 
  the 
  

   nasal, 
  at 
  right 
  angles 
  to 
  the 
  latter; 
  the 
  parietals, 
  when 
  

   present, 
  are 
  very 
  small, 
  separated 
  by 
  the 
  supraoccipital 
  ; 
  

   there 
  is 
  no 
  orbitosphenoid 
  ; 
  the 
  well-separated 
  alisphenoids 
  

   are 
  not 
  always 
  recognizable 
  as 
  distinct 
  elements 
  ; 
  a 
  basi- 
  

   sphenoid 
  is 
  present 
  and 
  the 
  myodome 
  has 
  an 
  osseous 
  roof; 
  

   the 
  opisthotic 
  is 
  absent, 
  and 
  the 
  epiotic 
  and 
  pterotic 
  are 
  

   produced 
  backwards 
  into 
  a 
  laminar 
  expansion, 
  with 
  which 
  a 
  

   similar 
  projection 
  of 
  the 
  exoccipital 
  is 
  usually 
  united. 
  The 
  

   post-temporal 
  is 
  usually 
  simple, 
  attached 
  to 
  the 
  epiotic 
  and 
  

   pterotic 
  lamina, 
  but 
  there 
  may 
  be 
  a 
  very 
  small 
  inner 
  fork 
  

   joining 
  the 
  exoccipital; 
  the 
  supra-cleithrum 
  is 
  reduced; 
  the 
  

   short 
  pectoral 
  radials 
  are 
  rigidly 
  united 
  with 
  the 
  hyper- 
  

   coracoid 
  and 
  hypocoracoid, 
  and 
  the 
  latter 
  is 
  expanded 
  ; 
  there 
  

   is 
  no 
  mesocoracoid. 
  The 
  vertebrae 
  are 
  numerous, 
  the 
  centra 
  

   and 
  arches 
  are 
  ankylosed, 
  and 
  the 
  ribs 
  and 
  epipleurals 
  are 
  

   inserted 
  together 
  on 
  the 
  transvere 
  processes, 
  the 
  ribs 
  com- 
  

   mencing 
  on 
  the 
  third 
  vertebra; 
  the 
  hypurals 
  are 
  reduced 
  in 
  

   number 
  and 
  ankylosed 
  with 
  the 
  last 
  centrum, 
  which 
  bears 
  a 
  

   prominent 
  horizontal 
  ridge 
  on 
  each 
  side. 
  

  

  The 
  Synentognathi 
  are 
  an 
  isolated 
  group, 
  without 
  evident 
  

   close 
  relationship 
  to 
  any 
  other 
  fishes, 
  but 
  showing 
  certain 
  

   resemblances 
  to 
  the 
  Microcyprini. 
  The 
  large 
  number 
  of 
  

   branchiostegals, 
  the 
  absence 
  of 
  spinous 
  fin-rays, 
  the 
  truly 
  

   abdominal 
  pelvic 
  fins, 
  the 
  mouth-structure, 
  and 
  other 
  cha- 
  

   racters 
  indicate 
  their 
  derivation 
  from 
  malacopterous 
  phy&o- 
  

   stomes 
  ; 
  they 
  do 
  not 
  appear 
  to 
  be 
  even 
  remotely 
  allied 
  to 
  the 
  

   Percesoces, 
  which 
  1 
  am 
  now 
  disposed 
  to 
  unite 
  with 
  the 
  

   l'ercomorphi, 
  for 
  I 
  cannot 
  believe 
  that 
  two 
  groups 
  so 
  pre- 
  

   cisely 
  similar 
  in 
  their 
  anatomy 
  are 
  not 
  closely 
  related, 
  nor 
  

   that 
  they 
  have 
  independently 
  acquired 
  the 
  combination 
  of 
  a 
  

   spinous 
  dorsal, 
  3 
  anal 
  spines, 
  15 
  branched 
  caudal 
  rays, 
  pelvic 
  

   fins 
  anterior, 
  of 
  a 
  spine 
  and 
  5 
  soft 
  rays, 
  and 
  24 
  vertebrae. 
  

  

  