﻿1864.] 
  POWBIE 
  — 
  FORFARSHIRE 
  FOSSILS. 
  421 
  

  

  sals, 
  two 
  pectorals, 
  two 
  ventrals, 
  and 
  one 
  anal 
  ; 
  two 
  rows 
  of 
  sub- 
  

   sidiary 
  or 
  dermal 
  spines 
  between 
  the 
  pectorals 
  and 
  ventrals 
  ; 
  anterior 
  

   dorsal 
  halfway 
  between 
  the 
  pectorals 
  and 
  ventrals 
  ; 
  scales 
  rather 
  small, 
  

   rhomboidal 
  ; 
  exterior 
  surface 
  smooth 
  ; 
  inner 
  carved, 
  tuberculated, 
  or 
  

   tuberculated 
  and 
  carved. 
  

  

  Climatius 
  reticulatus, 
  Agassiz. 
  

  

  Head 
  very 
  short 
  and 
  broad 
  ; 
  anterior 
  dorsal 
  short, 
  very 
  stout 
  ; 
  

   anterior 
  edge 
  curved; 
  posterior 
  edge 
  [nearly 
  straight, 
  all 
  the 
  spines 
  

   having 
  the 
  ridges 
  crenulated; 
  at 
  least 
  four 
  pairs 
  of 
  dermal 
  spines 
  

   between 
  the 
  pectorals 
  and 
  ventrals 
  ; 
  inner 
  surface 
  of 
  scales 
  tubercu- 
  

   lated 
  and 
  sculptured. 
  

  

  This 
  genus 
  and 
  species 
  was 
  so 
  named 
  by 
  Agassiz 
  from 
  a 
  Balrud- 
  

   dery 
  spine 
  (anterior 
  dorsal), 
  now 
  in 
  the 
  collection 
  at 
  Rossie 
  Priory. 
  

   Spines 
  and 
  other 
  fragments 
  of 
  this 
  Fish 
  are 
  by 
  no 
  means 
  rare 
  in 
  the 
  

   Forfarshire 
  Fish-bed 
  ; 
  but 
  good 
  and 
  nearly 
  entire 
  specimens 
  are 
  very 
  

   scarce 
  indeed, 
  while 
  none 
  have 
  yet 
  been 
  found 
  sufficiently 
  complete 
  

   to 
  elucidate 
  many 
  of 
  the 
  peculiarities 
  of 
  this 
  genus. 
  

  

  Such 
  specimens 
  as 
  I 
  have 
  procured 
  show 
  a 
  length 
  varying 
  from 
  

   five 
  to 
  eight 
  inches. 
  The 
  head 
  short, 
  stout, 
  rounded 
  anteriorly, 
  and 
  

   somewhat 
  depressed. 
  The 
  position 
  of 
  the 
  eye-orbits 
  is 
  obscure 
  ; 
  the 
  

   mouth 
  is 
  situated 
  entirely 
  below 
  the 
  head 
  ; 
  the 
  teeth 
  are 
  small, 
  co- 
  

   nical, 
  and 
  sharp 
  ; 
  the 
  body 
  appears 
  to 
  have 
  been 
  fusiform, 
  and 
  to 
  have 
  

   increased 
  slightly 
  in 
  thickness 
  from 
  the 
  head 
  backwards 
  to 
  the 
  in- 
  

   sertion 
  of 
  the 
  anterior 
  dorsal 
  spine, 
  its 
  depth 
  here 
  being 
  about 
  one- 
  

   fifth 
  the 
  entire 
  length, 
  thence 
  rapidly 
  to 
  have 
  tapered 
  to 
  the 
  com- 
  

   mencement 
  of 
  the 
  tail, 
  which 
  is 
  eminently 
  heterocercal 
  and 
  elongated, 
  

   having 
  the 
  caudal 
  fin 
  placed 
  entirely 
  below: 
  this 
  organ, 
  indeed, 
  

   appears 
  to 
  have 
  occupied 
  not 
  much 
  less 
  than 
  one-fourth 
  of 
  the 
  entire 
  

   length. 
  The 
  spines, 
  as 
  described 
  in 
  the 
  Decade, 
  are 
  stout 
  and 
  short, 
  

   striated 
  longitudinally 
  with 
  bold 
  rounded 
  ridges, 
  all 
  more 
  or 
  less 
  

   crenulated. 
  Dividing 
  the 
  Fish 
  longitudinally 
  into 
  five 
  equal 
  parts, 
  

   the 
  head 
  occupies 
  fully 
  the 
  first 
  fifth 
  : 
  the 
  second 
  fifth 
  terminates 
  

   nearly 
  in 
  the 
  centre 
  of 
  the 
  broad 
  base 
  of 
  the 
  anterior 
  dorsal 
  spine, 
  

   which 
  is 
  also 
  placed 
  about 
  midway 
  between 
  the 
  pectorals 
  and 
  ventrals; 
  

   it 
  is 
  short, 
  very 
  stout, 
  and 
  much 
  inclined 
  backwards 
  ; 
  the 
  anterior 
  edge 
  

   is 
  much 
  curved, 
  the 
  posterior 
  departing 
  but 
  little 
  from 
  a 
  straight 
  line 
  ; 
  

   the 
  grooves 
  and 
  crenate 
  ridges, 
  which 
  are 
  converging, 
  run 
  into 
  one 
  

   another 
  as 
  they 
  approach 
  its 
  apex. 
  The 
  posterior 
  dorsal 
  spine 
  rises 
  

   from 
  the 
  commencement 
  of 
  the 
  fourth 
  division 
  ; 
  it 
  is 
  much 
  more 
  

   slender 
  and 
  is 
  longer 
  than 
  the 
  anterior 
  ; 
  its 
  anterior 
  margin 
  is 
  perfectly 
  

   straight, 
  its 
  posterior 
  bulging 
  slightly 
  towards 
  its 
  point 
  of 
  insertion 
  ; 
  

   it 
  is 
  sharply 
  pointed, 
  and, 
  as 
  in 
  the 
  anterior 
  dorsal, 
  the 
  crenate 
  

   ridges 
  approach 
  and 
  run 
  into 
  one 
  another 
  as 
  they 
  near 
  the 
  apex. 
  

   The 
  anal 
  spine 
  much 
  resembles 
  the 
  posterior 
  dorsal 
  both 
  in 
  size 
  and 
  

   markings, 
  but 
  is 
  slightly 
  curved, 
  and 
  does 
  not 
  bulge 
  out 
  towards 
  its 
  

   base 
  ; 
  it 
  is 
  situated 
  rather 
  behind 
  the 
  anterior 
  dorsal. 
  The 
  ventrals, 
  

   short, 
  stout, 
  and 
  curved, 
  with 
  crenate 
  ridges, 
  are 
  situated 
  not 
  much 
  

   in 
  advance 
  of 
  the 
  anal. 
  The 
  pectorals 
  are 
  much 
  the 
  longest 
  spines 
  of 
  

   this 
  species, 
  being 
  nearly 
  equal 
  in 
  thickness 
  to 
  the 
  anterior 
  dorsal, 
  

  

  