﻿176 
  ACTINOPTERYGII. 
  

  

  Germs 
  LEGNONOTUS, 
  Egerton. 
  

   [Ann. 
  Mag. 
  Nat. 
  Hist. 
  [2] 
  vol. 
  iii. 
  1854, 
  p. 
  435.] 
  

  

  Trunk 
  gradually 
  tapering 
  from 
  the 
  occiput 
  backwards 
  or 
  the 
  

   dorsal 
  margin 
  only 
  slightly 
  arcuate. 
  Marginal 
  teeth 
  very 
  long 
  and 
  

   much 
  crowded. 
  Dorsal 
  fin 
  extending 
  almost 
  the 
  whole 
  length 
  of 
  

   the 
  back, 
  and 
  all 
  the 
  rays, 
  except 
  perhaps 
  anteriorly, 
  distally 
  

   bifurcating. 
  Scales 
  apparently 
  covering 
  the 
  whole 
  of 
  the 
  trunk, 
  in 
  

   regular 
  series, 
  those 
  of 
  the 
  middle 
  of 
  the 
  flank 
  much 
  deeper 
  than 
  

   broad. 
  Lateral 
  line 
  forming 
  a 
  conspicuous 
  ridge. 
  

  

  Legnonotus 
  cothamensis, 
  Egerton. 
  

   1854-55. 
  Legnonotus 
  cothamensis, 
  Sir 
  P. 
  Egerton, 
  loo. 
  cit. 
  p. 
  435, 
  and 
  

   Figs, 
  and 
  Descript. 
  Brit. 
  Organic 
  Remains 
  (Mem. 
  Geol. 
  Surv.), 
  

   dec. 
  viii. 
  no. 
  7, 
  p. 
  4, 
  pi. 
  vii. 
  figs. 
  9-12. 
  

  

  Type. 
  Imperfect 
  trunk 
  ; 
  Bristol 
  Museum. 
  

  

  The 
  type 
  species, 
  attaining 
  a 
  length 
  of 
  about 
  0*06. 
  Marginal 
  

   teeth 
  bluntly 
  pointed 
  ; 
  operculum 
  ornamented 
  with 
  large, 
  flattened 
  

   tubercles. 
  Dorsal 
  fin 
  comprising 
  about 
  30 
  rays. 
  Scales 
  compara- 
  

   tively 
  large, 
  smooth, 
  but 
  coarsely 
  serrated; 
  principal 
  scales 
  of 
  

   lateral 
  line 
  about 
  two-thirds 
  as 
  broad 
  as 
  deep. 
  

  

  Form. 
  Sf 
  Loc. 
  Bhaetic 
  (Cotham 
  Marble) 
  : 
  Aust 
  Cliff, 
  Gloucester- 
  

   shire. 
  

  

  P. 
  1092. 
  Three 
  small 
  slabs 
  exhibiting 
  portions 
  of 
  jaws 
  associated 
  

   with 
  a 
  mass 
  of 
  scales, 
  bone-fragments, 
  and 
  ring-vertebrae. 
  

  

  Egerton 
  Coll. 
  

  

  Genus 
  MACROSEMIUS, 
  Agassiz. 
  

  

  [Neues 
  Jahrb. 
  1834, 
  p. 
  387.] 
  

  

  Syn. 
  Bisticholepis, 
  V. 
  Thiolliere, 
  Ann. 
  Soc. 
  Sci. 
  Phys. 
  & 
  Nat. 
  Lyon, 
  

   [2] 
  vol. 
  iii. 
  1850, 
  p. 
  136, 
  and 
  Poiss. 
  Foss. 
  Bugey, 
  pt. 
  ii. 
  1873, 
  

   p. 
  14. 
  

  

  Trunk 
  gradually 
  tapering 
  from 
  the 
  occiput 
  backwards; 
  head 
  

   large, 
  snout 
  acute. 
  Teeth 
  much 
  elongated, 
  closely 
  arranged. 
  

   Notochord 
  persistent, 
  without 
  ring-vertebrae; 
  ribs 
  ossified. 
  Fins 
  

   consisting 
  of 
  very 
  robust, 
  bifurcating 
  rays, 
  without 
  fulcra 
  except 
  in 
  

   the 
  caudal; 
  pectoral 
  fins 
  much 
  larger 
  than 
  the 
  pelvic 
  pair; 
  dorsal 
  

   fin 
  arising 
  immediately 
  behind 
  the 
  occiput 
  and 
  extending 
  con- 
  

   tinuously 
  to 
  the 
  caudal 
  pedicle 
  ; 
  anal 
  fin 
  small 
  ; 
  caudal 
  fin 
  rounded. 
  

   Scales 
  thin 
  and 
  more 
  or 
  less 
  pectinated, 
  with 
  peg-and-socket 
  articu- 
  

   lation, 
  and 
  apparently 
  wanting 
  towards 
  the 
  dorsal 
  margin 
  ; 
  scales 
  

  

  