﻿SEMIOtfOTID^. 
  81 
  

  

  the 
  neural 
  arches 
  in 
  the 
  abdominal 
  region 
  are 
  separate 
  and 
  not 
  

   anchylosed 
  with 
  the 
  neural 
  spine 
  ; 
  the 
  ribs 
  are 
  long 
  and 
  slender, 
  

   apparently 
  extending 
  to 
  the 
  ventral 
  border. 
  

  

  In 
  the 
  pectoral 
  arch 
  the 
  clavicle 
  is 
  relatively 
  much 
  expanded, 
  

   though 
  pointed, 
  below 
  ; 
  and 
  it 
  tapers 
  irregularly 
  above 
  where 
  over- 
  

   lapped 
  by 
  the 
  supraclavicle. 
  Immediately 
  behind 
  the 
  longitudinal 
  

   bend 
  in 
  the 
  element 
  the 
  outer 
  surface 
  is 
  covered 
  with 
  a 
  rugose 
  

   thickening, 
  marked 
  with 
  vermiculating 
  rows 
  of 
  denticles 
  of 
  ganoine. 
  

   The 
  supraclavicle 
  is 
  narrow, 
  about 
  half 
  as 
  long 
  as 
  the 
  clavicle, 
  

   and 
  firmly 
  articulated 
  at 
  its 
  thickened 
  upper 
  end 
  with 
  the 
  small, 
  

   almost 
  club-shaped 
  post-temporal. 
  The 
  basal 
  bones 
  of 
  the 
  pectoral 
  

   fin 
  are 
  large 
  and 
  much 
  elongated, 
  slightly 
  expanded 
  at 
  each 
  end, 
  

   and 
  more 
  than 
  five 
  in 
  number. 
  The 
  pelvic 
  fin-supports 
  are 
  unknown. 
  

   Biserial 
  fulcra 
  are 
  present 
  on 
  the 
  anterior 
  border 
  both 
  of 
  the 
  paired 
  

   and 
  median 
  fins 
  ; 
  and 
  the 
  supports 
  of 
  the 
  dorsal 
  and 
  anal 
  are 
  much 
  

   enlarged 
  beneath 
  them. 
  

  

  The 
  supratemporal 
  plates 
  vary 
  much 
  in 
  arrangement 
  in 
  different 
  

   species 
  of 
  Lepidotus, 
  but 
  they 
  always 
  overlap 
  both 
  the 
  cranial 
  roof- 
  

   bones 
  and 
  the 
  most 
  anterior 
  dorsal 
  scales. 
  In 
  L. 
  latifrons 
  there 
  is 
  

   one 
  not 
  quite 
  symmetrical 
  pair 
  of 
  outer 
  plates, 
  occupying 
  the 
  space 
  

   between 
  the 
  operculum, 
  squamosal, 
  and 
  parietal 
  on 
  each 
  side 
  ; 
  and 
  

   there 
  are 
  three 
  symmetrically 
  arranged 
  plates, 
  no 
  larger 
  than 
  

   ordinary 
  scales, 
  apposed 
  to 
  the 
  hinder 
  margin 
  of 
  the 
  parietals. 
  In 
  

   L. 
  mantelli 
  the 
  supratemp 
  orals 
  are 
  in 
  three 
  pairs, 
  the 
  two 
  outer 
  

   ones 
  corresponding 
  to 
  the 
  single 
  outer 
  pair 
  in 
  L. 
  latifrons. 
  In 
  

   L. 
  elvensis, 
  as 
  already 
  described 
  by 
  Quenstedt, 
  the 
  supratemporal 
  

   series 
  consists 
  of 
  a 
  single 
  pair 
  of 
  large 
  plates, 
  as 
  in 
  Amia. 
  

  

  There 
  is 
  a 
  series 
  of 
  postclavicular 
  scales, 
  but 
  only 
  two 
  on 
  each 
  

   side 
  are 
  much 
  enlarged. 
  These 
  two 
  scales 
  extend 
  the 
  whole 
  depth 
  

   of 
  the 
  flank, 
  the 
  uppermost 
  being 
  longest 
  and 
  narrowest. 
  There 
  

   are 
  also 
  three 
  enlarged 
  scales 
  round 
  the 
  anus, 
  which 
  seems 
  to 
  have 
  

   been 
  mesially 
  placed 
  ; 
  their 
  exposed 
  portion 
  is 
  cycloidal, 
  and 
  the 
  

   hinder 
  margin 
  usually 
  serrated. 
  Nearly 
  all 
  the 
  other 
  scales 
  are 
  in 
  

   regular 
  series, 
  and 
  those 
  of 
  the 
  flank 
  are 
  united 
  by 
  a 
  feeble 
  peg- 
  

   and-socket 
  articulation 
  ; 
  a 
  single 
  row 
  of 
  scales, 
  however, 
  at 
  the 
  base 
  

   of 
  the 
  dorsal, 
  anal, 
  and 
  caudal 
  fins 
  does 
  not 
  conform 
  to 
  the 
  regular 
  

   flank-series, 
  but 
  is 
  directly 
  related 
  to 
  the 
  fin-rays 
  and 
  fulcra. 
  All 
  

   the 
  flank-scales 
  are 
  deeply 
  overlapping, 
  and 
  most 
  of 
  them 
  exhibit 
  

   a 
  forward 
  production 
  both 
  of 
  the 
  antero-superior 
  and 
  anteroinferior 
  

   angle 
  ; 
  in 
  some 
  of 
  those 
  of 
  the 
  foremost 
  series 
  the 
  overlapped 
  

   portion 
  is 
  wider 
  than 
  the 
  exposed 
  area. 
  The 
  dorsal 
  and 
  ventral 
  

   ridge-scales 
  are 
  never 
  much 
  enlarged 
  ; 
  they 
  are 
  inconspicuous 
  in 
  

   the 
  more 
  robust 
  species, 
  but 
  appear 
  as 
  a 
  serrated 
  ridge 
  on 
  the 
  back 
  

   in 
  those 
  which 
  are 
  more 
  laterally 
  compressed. 
  

  

  paet 
  in. 
  g 
  

  

  