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  ACTINOPTERYGII. 
  

  

  Genus 
  MESTURUS, 
  Wagner. 
  

   [Abh. 
  k. 
  bay. 
  Akad. 
  Wiss., 
  math.-phys. 
  CI. 
  vol. 
  ix. 
  1862, 
  p. 
  338.] 
  

  

  Trunk 
  discoidal, 
  abruptly 
  produced 
  into 
  a 
  small 
  and 
  short 
  caudal 
  

   pedicle. 
  Head 
  and 
  opercular 
  bones 
  externally 
  ornamented 
  with 
  

   granulations; 
  teeth 
  with 
  a 
  crimped 
  and 
  usually 
  indented 
  coronal 
  

   apex 
  ; 
  vomerine 
  teeth 
  arranged 
  in 
  three 
  principal 
  series, 
  with 
  a 
  

   varying 
  number 
  of 
  irregular, 
  small, 
  intercalated 
  series 
  ; 
  splenial 
  

   dentition 
  comprising 
  one 
  principal 
  series 
  of 
  teeth, 
  with 
  about 
  two 
  

   inner 
  and 
  several 
  outer 
  irregular 
  series 
  of 
  smaller 
  teeth. 
  Fin-rays 
  

   robust, 
  closely 
  articulated, 
  and 
  much 
  divided 
  distally. 
  Pelvic 
  fins 
  

   present 
  ; 
  dorsal 
  and 
  anal 
  fins 
  deep 
  throughout 
  their 
  extent, 
  not 
  

   specially 
  elevated 
  in 
  front, 
  and 
  the 
  former 
  occupying 
  about 
  the 
  

   hinder 
  half 
  of 
  the 
  back 
  ; 
  caudal 
  fin 
  fan-shaped, 
  having 
  a 
  sinuously 
  

   convex 
  hinder 
  margin, 
  and 
  nearly 
  surrounding 
  the 
  short 
  caudal 
  

   pedicle. 
  Scales 
  robust 
  and 
  covering 
  the 
  whole 
  of 
  the 
  trunk 
  ; 
  their 
  

   upper 
  and 
  lower 
  margins 
  united 
  by 
  interlocking 
  digitations, 
  and 
  

   their 
  external 
  surface 
  tuberculated. 
  

  

  Mesturus 
  verrucosus, 
  Wagner. 
  

  

  [Plate 
  XV.] 
  

  

  1862. 
  Mesturus 
  verrucosus, 
  A. 
  Wagner, 
  Abh. 
  k. 
  bay. 
  Akad. 
  Wiss., 
  

   math.-phys. 
  CI. 
  vol. 
  ix. 
  p. 
  338 
  ; 
  pi. 
  iii. 
  fig. 
  1. 
  

  

  Type. 
  Nearly 
  complete 
  fish 
  ; 
  Paleeontological 
  Museum, 
  Munich. 
  

  

  The 
  type 
  species, 
  attaining 
  a 
  length 
  of 
  about 
  0*5. 
  Maximum 
  

   depth 
  of 
  trunk 
  considerably 
  exceeding 
  its 
  length 
  from 
  the 
  scapular 
  

   arch 
  to 
  the 
  base 
  of 
  the 
  caudal 
  pedicle, 
  and 
  head 
  with 
  opercular 
  

   apparatus 
  occupying 
  nearly 
  one-third 
  of 
  the 
  total 
  length 
  of 
  the 
  fish 
  

   (including 
  caudal 
  fin). 
  [Dentition 
  unsatisfactorily 
  known, 
  but] 
  the 
  

   teeth 
  of 
  the 
  outermost 
  series 
  on 
  the 
  splenial 
  little 
  inferior 
  in 
  size 
  

   to 
  those 
  of 
  the 
  principal 
  series. 
  Dorsal 
  fin 
  with 
  32 
  rays, 
  arising 
  

   at 
  the 
  middle 
  of 
  the 
  back 
  behind 
  its 
  highest 
  point 
  ; 
  [anal 
  fin 
  

   incompletely 
  known]. 
  Tubercular 
  ornamentation 
  of 
  the 
  scales 
  

   fine 
  and 
  closely 
  arranged 
  compared 
  with 
  that 
  of 
  the 
  head-bones, 
  

   except 
  in 
  the 
  anterior 
  half 
  of 
  the 
  lateral 
  line, 
  where 
  the 
  tubercles 
  

   form 
  a 
  series 
  of 
  irregular 
  excrescences. 
  All 
  the 
  principal 
  scales 
  

   exhibiting 
  fine 
  structural 
  lines 
  radiating 
  backwards 
  from 
  a 
  point 
  

   on 
  their 
  anterior 
  margin, 
  beneath 
  the 
  tubercular 
  ornamentation. 
  

   The 
  vertical 
  series 
  of 
  scales 
  irregularly 
  bifurcating 
  towards 
  the 
  

   whole 
  of 
  the 
  dorsal 
  margin 
  and 
  towards 
  the 
  caudal 
  half 
  of 
  the 
  

   ventral 
  margin. 
  

  

  Form. 
  &f 
  Loc. 
  Lower 
  Kimmeridgian 
  (Lithographic 
  Stone) 
  : 
  Bavaria. 
  

  

  