﻿198 
  ACTINOPTERYGII. 
  

  

  Vomerine 
  teeth 
  in 
  five, 
  and 
  splenial 
  teeth 
  

   in 
  four 
  regular 
  longitudinal 
  series 
  ; 
  

   scales 
  covering 
  whole 
  of 
  trunk, 
  and 
  

   none 
  united 
  with 
  jagged 
  sutures 
  .... 
  Gyrodus 
  (p. 
  233). 
  

   Vomerine 
  teeth 
  in 
  five, 
  and 
  splenial 
  teeth 
  

   in 
  three 
  regular 
  longitudinal 
  series 
  ; 
  

   squamation 
  confined 
  to 
  region 
  in 
  

   advance 
  of 
  median 
  fins 
  : 
  caudal 
  fin 
  

  

  scarcely 
  forked 
  Stemmatodus 
  (p. 
  248). 
  

  

  Oral 
  surface 
  of 
  vomer 
  convex 
  from 
  side 
  to 
  

   side, 
  and 
  teeth 
  in 
  five 
  regular 
  longi- 
  

   tudinal 
  series 
  ; 
  splenial 
  teeth 
  in 
  three 
  

   series, 
  the 
  outer 
  sometimes 
  in 
  part 
  

   subdivided, 
  the 
  inner 
  sometimes 
  

   irregularly 
  supplemented 
  ; 
  squamation 
  

   confined 
  to 
  region 
  in 
  advance 
  of 
  

  

  median 
  fins 
  Ccelodus 
  (p. 
  249). 
  

  

  (c.) 
  Splenial 
  dentition 
  comparatively 
  degene- 
  

   rate, 
  restricted 
  to 
  a 
  space 
  well 
  within 
  

   outer 
  margin, 
  and 
  number 
  of 
  longitu- 
  

   dinal 
  series 
  inconstant 
  ; 
  no 
  dermal 
  

   spines. 
  

   Vomerine 
  teeth 
  irregular, 
  in 
  from 
  three 
  to 
  

   five 
  longitudinal 
  series 
  ; 
  squamation 
  

   confined 
  to 
  region 
  in 
  advance 
  of 
  

  

  median 
  fins 
  Anomoeodus 
  (p. 
  258). 
  

  

  (d.) 
  Abnormal 
  genera 
  with 
  median 
  occipital 
  

   spine, 
  and 
  more 
  or 
  less 
  spinous 
  pectoral 
  

   arch. 
  

   Vomerine 
  teeth 
  apparently 
  in 
  five, 
  and 
  

   splenial 
  teeth 
  in 
  three 
  regular 
  longi- 
  

   tudinal 
  series 
  ; 
  clavicular 
  spines 
  large 
  ; 
  

  

  scales 
  wanting 
  Coccodus 
  (p. 
  266). 
  

  

  Imperfectly 
  known, 
  but 
  greater 
  portion 
  of 
  

   trunk 
  covered 
  with 
  large, 
  rhombic, 
  

  

  keeled 
  scutes 
  Xenopholis 
  (p. 
  269). 
  

  

  II. 
  Neural 
  and 
  haemal 
  arches 
  of 
  axial 
  skeleton 
  

   of 
  trunk 
  expanding 
  and 
  completely 
  encir- 
  

   cling 
  the 
  notochord. 
  

   Vomerine 
  teeth 
  in 
  five, 
  and 
  splenial 
  teeth 
  in 
  

   three 
  regular 
  longitudinal 
  series 
  ; 
  caudal 
  

   pedicle 
  very 
  short, 
  and 
  fin 
  fan-shaped 
  ; 
  

  

  squamation 
  variable 
  Palceobalistum 
  (p. 
  270). 
  

  

  Dentition 
  as 
  in 
  Talczobalistum 
  ; 
  caudal 
  pedicle 
  

   slender 
  and 
  fin 
  slightly 
  forked 
  ; 
  squama- 
  

   tion 
  confined 
  to 
  region 
  in 
  advance 
  of 
  

   median 
  fins 
  Pycnodus 
  (p. 
  275). 
  

  

  