﻿OLIGOPLEURIDJE. 
  493 
  

  

  deeper 
  than 
  long, 
  the 
  others 
  mostly 
  as 
  long 
  as 
  deep. 
  Pelvic 
  fins 
  

   arising 
  midway 
  between 
  the 
  pectorals 
  and 
  the 
  anal 
  ; 
  dorsal 
  fin 
  

   scarcely 
  larger 
  than 
  the 
  anal, 
  and 
  arising 
  slightly 
  in 
  advance 
  of 
  the 
  

   latter. 
  

  

  Form. 
  Sf 
  Loc. 
  Lower 
  Kimmeridgian 
  (Lithographic 
  Stone) 
  : 
  Cirin, 
  

   Ain, 
  Prance. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Oligopleurus 
  vectensis, 
  A. 
  S. 
  Woodward. 
  

  

  1890. 
  Oligopleurus 
  vectensis, 
  A. 
  S. 
  Woodward, 
  Proc. 
  Zool. 
  Soc. 
  p. 
  346, 
  

   pi. 
  xxviii. 
  fig. 
  1 
  (? 
  pi. 
  xxviii. 
  figs. 
  2-4, 
  pi. 
  xxix. 
  figs. 
  1-3). 
  

  

  Type. 
  Skull 
  with 
  anterior 
  vertebras 
  ; 
  British 
  Museum. 
  

  

  A 
  species 
  attaining 
  a 
  size 
  at 
  least 
  twice 
  as 
  large 
  as 
  the 
  type, 
  

   known 
  only 
  by 
  the 
  head 
  and 
  anterior 
  vertebras. 
  The 
  vertebras 
  are 
  

   much 
  deeper 
  in 
  proportion 
  to 
  their 
  length 
  than 
  those 
  of 
  0. 
  esocinus. 
  

  

  Form. 
  4" 
  Loc. 
  Wealden 
  : 
  Isle 
  of 
  Wight. 
  (?) 
  Purbeckian 
  : 
  Dorset- 
  

   shire. 
  

  

  42013. 
  Type 
  specimen, 
  described 
  and 
  figured 
  loc. 
  cit. 
  ; 
  Wealden, 
  

  

  Isle 
  of 
  Wight. 
  Purchased, 
  1870. 
  

  

  42014. 
  Fragmentary 
  portions 
  of 
  head 
  and 
  anterior 
  vertebras 
  in 
  

  

  sandstone, 
  noticed 
  loc. 
  cit. 
  ; 
  Wealden, 
  Isle 
  of 
  Wight. 
  

  

  Purchased, 
  1870. 
  

   The 
  undermentioned 
  specimens 
  from 
  the 
  Purbeck 
  Beds 
  of 
  Swanage 
  

   are 
  only 
  provisionally 
  assigned 
  to 
  this 
  species. 
  The 
  large 
  dentary 
  

   bone 
  (No. 
  36083) 
  seems 
  to 
  be 
  comparatively 
  shorter 
  and 
  stouter 
  

   than 
  that 
  of 
  the 
  type 
  specimen 
  of 
  O. 
  vectensis 
  ; 
  otherwise 
  it 
  is 
  

   difficult 
  to 
  recognize 
  any 
  mark 
  of 
  specific 
  distinction 
  between 
  the 
  

   Wealden 
  and 
  Purbeckian 
  fossils. 
  

  

  40433. 
  Immature 
  fish 
  0-2 
  in 
  length, 
  described 
  and 
  figured 
  loc. 
  cit. 
  

   p. 
  349, 
  pi. 
  xxix. 
  fig. 
  3. 
  The 
  length 
  of 
  the 
  head 
  with 
  

   opercular 
  apparatus 
  is 
  contained 
  slightly 
  more 
  than 
  four 
  

   times, 
  and 
  the 
  depth 
  of 
  the 
  trunk 
  at 
  the 
  pectoral 
  arch 
  

   nearly 
  seven 
  times 
  in 
  the 
  total 
  length 
  of 
  the 
  fish. 
  The 
  

   origin 
  of 
  the 
  dorsal 
  fin 
  appears 
  to 
  be 
  exactly 
  opposite 
  to 
  

   that 
  of 
  the 
  anal, 
  and 
  these 
  two 
  fins 
  are 
  about 
  equal 
  in 
  

   size. 
  The 
  caudal 
  pedicle 
  seems 
  to 
  have 
  been 
  relatively 
  

   more 
  slender 
  than 
  in 
  0. 
  esocinus. 
  Cunnington 
  Coll. 
  (?). 
  

  

  P. 
  4219. 
  Imperfect 
  head 
  and 
  anterior 
  vertebras, 
  described 
  and 
  

   figured 
  as 
  Lepidotus 
  minor 
  by 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  

   pt. 
  i. 
  p. 
  269, 
  pi. 
  xxix 
  c. 
  fig. 
  12, 
  assigned 
  to 
  Oligopleurus 
  

   vectensis 
  by 
  the 
  present 
  writer, 
  loc. 
  cit. 
  p. 
  346, 
  pi. 
  xxviii. 
  

  

  