﻿Arthur. 
  — 
  On 
  the 
  Brown 
  Trout 
  introduced 
  into 
  Otarjo, 
  285 
  

  

  transverse 
  row, 
  accordiug 
  to 
  Giintlier, 
  and 
  the 
  pyloric 
  caeca 
  fewer 
  on 
  an 
  

   average 
  by 
  9. 
  As 
  yet, 
  I 
  have 
  made 
  no 
  examination 
  of 
  the 
  number 
  of 
  

   vertebrae, 
  so 
  my 
  comparison 
  in 
  that 
  and 
  one 
  or 
  two 
  other 
  particulars 
  is 
  

   incomplete. 
  

  

  With 
  regard 
  to 
  the 
  features 
  of 
  the 
  head, 
  as 
  to 
  structure, 
  my 
  remarks 
  will 
  

   refer 
  to 
  two 
  heads, 
  both 
  of 
  females— 
  one 
  of 
  a 
  fish, 
  i^Vos. 
  in 
  weight, 
  taken 
  

   in 
  the 
  Lee 
  in 
  October, 
  1877 
  ; 
  and 
  the 
  other 
  of 
  a 
  fish 
  over 
  6lbs. 
  in 
  

   weight, 
  caught 
  in 
  the 
  Upper 
  Taieri 
  Eiver 
  in 
  March, 
  1878. 
  Fac-similes* 
  

   of 
  these 
  are 
  represented 
  on 
  pi. 
  XIII., 
  fig. 
  1 
  and 
  fig. 
  2 
  fS. 
  fario) 
  

   accompanying 
  this 
  paper. 
  In 
  fig, 
  1 
  the 
  posterior 
  end 
  of 
  maxillary 
  is 
  2/^ 
  

   inches 
  from 
  the 
  snout, 
  and 
  at 
  its 
  greatest 
  width 
  measures 
  -/-§■ 
  of 
  an 
  

   inch. 
  The 
  lower 
  limb 
  is 
  strong 
  and 
  prominent, 
  and 
  the 
  whole 
  bone 
  

   characteristically 
  coarse 
  and 
  large. 
  + 
  Of 
  the 
  gill-covers, 
  the 
  posterior 
  

   margin 
  of 
  the 
  operculum 
  forms 
  nearly 
  a 
  right-angle 
  with 
  the 
  junc- 
  

   tion 
  line 
  of 
  the 
  operculum 
  and 
  suboperculum. 
  This 
  junction 
  or 
  joint 
  

   of 
  the 
  operculum 
  and 
  suboperculum 
  forms 
  an 
  angle 
  of 
  nearly 
  23° 
  

   with 
  the 
  axis 
  of 
  the 
  body 
  of 
  the 
  fish. 
  The 
  suboperculum 
  in 
  shape 
  

   roughly 
  resembles 
  or 
  approaches 
  a 
  rectangle, 
  the 
  posterior 
  lower 
  margin 
  

   forming 
  a 
  blunt 
  rounded 
  angle. 
  The 
  average 
  length, 
  or 
  middle 
  length 
  

   of 
  this 
  bone^ 
  is 
  If*^ 
  inches, 
  and 
  the 
  middle 
  width 
  f 
  of 
  an 
  inch. 
  The 
  

   interoperculum 
  forms 
  rather 
  less 
  than 
  a 
  right 
  angle 
  at 
  its 
  junction 
  with 
  the 
  

   suboperculum, 
  this 
  line 
  making 
  with 
  the 
  axis 
  of 
  the 
  body 
  of 
  the 
  fish 
  an 
  

   angle 
  of 
  47°. 
  The 
  lower 
  margin 
  is 
  flatly 
  rounded 
  and 
  continuous, 
  nearly 
  in 
  

   line 
  with 
  lower 
  margin 
  of 
  suboperculum, 
  and 
  the 
  anterior 
  extremity 
  nearly 
  

   semi-circular. 
  The 
  preoperculum 
  is 
  sinuously 
  rounded 
  in 
  margin, 
  and 
  

   covers 
  about 
  one 
  half 
  of 
  the 
  surface 
  of 
  the 
  interoperculum. 
  

  

  In 
  the 
  case 
  of 
  fig. 
  2, 
  the 
  posterior 
  end 
  of 
  maxillary 
  measures 
  2|-^ 
  inches 
  

   from 
  the 
  snout, 
  and 
  the 
  body 
  of 
  the 
  bone 
  very 
  nearly 
  |- 
  an 
  inch 
  at 
  its 
  greatest 
  

   width. 
  It 
  is 
  approximately 
  similar 
  to 
  the 
  maxillary 
  of 
  fig. 
  1, 
  the 
  Lee 
  

   Stream 
  trout, 
  only 
  the 
  posterior 
  extremity 
  is 
  much 
  more 
  rounded, 
  this 
  fish 
  

   being 
  evidently 
  an 
  older 
  individual. 
  The 
  end 
  projects 
  -f-^ 
  in. 
  behind 
  

   vertical, 
  from 
  posterior 
  margin 
  of 
  orbit. 
  The 
  posterior 
  margin 
  of 
  the 
  

   operculum 
  forms 
  nearly 
  a 
  right-angle 
  with 
  the 
  junction 
  of 
  the 
  operculum 
  

   and 
  suboperculum. 
  This 
  line 
  or 
  joint 
  of 
  operculum 
  and 
  suboperculum 
  

   forms 
  an 
  angle 
  with 
  the 
  axis 
  of 
  the 
  body 
  of 
  the 
  fish 
  of 
  nearly 
  26°. 
  The 
  

   suboperculum 
  in 
  shape 
  roughly 
  approaches 
  a 
  four-sided 
  figure, 
  almost 
  a 
  

   rectangle, 
  the 
  posterior 
  lower 
  margin 
  forming 
  a 
  blunt 
  angle 
  with 
  a 
  sharp 
  

   curve 
  at 
  the 
  apex. 
  The 
  middle 
  length 
  of 
  this 
  bone 
  is 
  If'-^ 
  inches, 
  and 
  its 
  

   middle 
  width 
  -| 
  inch. 
  The 
  interoperculum 
  forms 
  at 
  its 
  junction 
  with 
  the 
  

  

  * 
  [Reduced 
  one-half 
  from 
  author's 
  original 
  drawings.] 
  

   t 
  It 
  projects 
  -A- 
  in. 
  behind 
  the 
  vertical, 
  from 
  posterior 
  margin 
  of 
  orbit. 
  

  

  