﻿\)b 
  ACTINOPTEEYGII. 
  

  

  bones 
  about 
  one-third 
  as 
  long 
  as 
  the 
  frontals, 
  which 
  are 
  three 
  times 
  

   as 
  long 
  as 
  their 
  maximum 
  width, 
  narrow 
  in 
  front, 
  and 
  united 
  by 
  a 
  

   nearly 
  straight 
  median 
  suture; 
  mandibular 
  symphysis 
  not 
  much 
  

   deepened 
  or 
  extended. 
  Marginal 
  teeth 
  on 
  much 
  elongated 
  pedicles, 
  

   the 
  crown 
  obtusely 
  conical 
  in 
  the 
  lower 
  jaw 
  ; 
  inner 
  teeth 
  mostly 
  

   larger 
  and 
  obtuse, 
  but 
  on 
  moderately 
  long 
  pedicles. 
  Pin-fulcra 
  

   very 
  large, 
  the 
  principal 
  dorsal 
  fulcra 
  more 
  than 
  half 
  as 
  long 
  as 
  the 
  

   anterior 
  dorsal 
  fin-rays 
  ; 
  pelvic 
  fins 
  arising 
  midway 
  between 
  the 
  

   pectorals 
  and 
  the 
  anal; 
  dorsal 
  and 
  anal 
  fins 
  deeper 
  than 
  long. 
  

   Scales 
  smooth, 
  those 
  of 
  the 
  flank 
  coarsely 
  serrated 
  in 
  the 
  young, 
  

   partly 
  without 
  serrations, 
  partly 
  with 
  few 
  irregular 
  denticulations 
  

   in 
  the 
  adult; 
  scales 
  of 
  lateral 
  line 
  notched; 
  dorsal 
  ridge-scales 
  

   acutely 
  pointed 
  and 
  prominent. 
  

  

  The 
  large 
  collection 
  catalogued 
  below 
  seems 
  to 
  indicate 
  that 
  the 
  

   individuals 
  of 
  this 
  species 
  grow 
  stouter 
  with 
  age, 
  besides 
  losing 
  the 
  

   conspicuous 
  serrations 
  on 
  the 
  scales 
  of 
  the 
  flank. 
  A 
  restoration 
  of 
  

   a 
  typical 
  fish 
  is 
  attempted 
  in 
  the 
  accompanying 
  fig. 
  22, 
  of 
  one-half 
  

   the 
  natural 
  size, 
  the 
  only 
  part 
  remaining 
  doubtful 
  being 
  the 
  

   arrangement 
  of 
  the 
  bones 
  of 
  the 
  snout. 
  

  

  A 
  small 
  fish 
  from 
  the 
  Wealden 
  of 
  the 
  Deister, 
  Hanover, 
  assigned 
  

   to 
  this 
  species 
  by 
  C. 
  Struckmann 
  (Wealdenbild. 
  Hannover, 
  1880, 
  

   p. 
  86), 
  has 
  received 
  the 
  provisional 
  name 
  of 
  Lepidotus 
  strucJcmanni 
  

   (W. 
  Branco, 
  loc. 
  cit. 
  p. 
  368, 
  pi. 
  vi. 
  fig. 
  1). 
  

  

  Form. 
  Sf 
  Loc. 
  Purbeckian 
  : 
  Dorsetshire. 
  

  

  The 
  following 
  specimens 
  were 
  all 
  obtained 
  from 
  the 
  neighbour- 
  

   hood 
  of 
  Swanage 
  : 
  — 
  

  

  19006. 
  Pine 
  adult 
  fish, 
  with 
  imperfect 
  head, 
  about 
  034 
  in 
  length 
  

   and 
  0*12 
  in 
  maximum 
  depth. 
  The 
  dorsal 
  fin-fulcra 
  are 
  

   especially 
  robust, 
  four 
  pairs 
  having 
  a 
  separate 
  insertion 
  

   in 
  advance 
  of 
  the 
  anterior 
  ray 
  ; 
  and 
  the 
  principal 
  flank- 
  

   scales 
  exhibit 
  only 
  feeble 
  coarse 
  denticulations 
  in 
  their 
  

   inferior 
  half. 
  Purchased, 
  1845. 
  

  

  41157. 
  Equally 
  large 
  individual, 
  wanting 
  the 
  caudal 
  and 
  paired 
  

   fins, 
  displaying 
  some 
  of 
  the 
  ribs 
  and 
  median 
  fin-supports, 
  

   and 
  the 
  squamation 
  of 
  the 
  left 
  side 
  from 
  the 
  inner 
  aspect. 
  

   Some 
  of 
  the 
  left 
  opercular 
  and 
  facial 
  bones 
  are 
  also 
  shown 
  

   from 
  within, 
  and 
  the 
  mandibular 
  ramus 
  exhibits 
  some 
  of 
  

   the 
  splenial 
  teeth 
  on 
  long 
  pedicles 
  posteriorly. 
  

  

  Purchased, 
  1868. 
  

  

  42308. 
  Somewhat 
  larger 
  fish, 
  the 
  squamation 
  shown 
  only 
  in 
  im- 
  

   pression 
  and 
  some 
  of 
  the 
  cranial 
  and 
  facial 
  bones 
  from 
  

   the 
  inner 
  aspect. 
  Purchased, 
  1870. 
  

  

  