﻿428 
  ACTINOPTERYGil. 
  

  

  in 
  the 
  Palseontological 
  Museum, 
  Munich 
  (F. 
  Bassani, 
  Denkschr. 
  k. 
  

   Akad. 
  Wiss., 
  math.-naturw. 
  CI. 
  vol. 
  xlv. 
  1882, 
  p. 
  264 
  ; 
  K. 
  A. 
  von 
  

   Zittel, 
  Handb. 
  Palseont. 
  vol. 
  iii. 
  1887, 
  p. 
  221). 
  

  

  Aspidorhynchus 
  walchneri 
  is 
  another 
  undefined 
  name 
  applied 
  to 
  

   fragments 
  of 
  the 
  skull 
  of 
  Belonorhynchus 
  from 
  the 
  Upper 
  Lias 
  of 
  

   Baden 
  and 
  Wiirtemberg 
  (L. 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  i. 
  1833, 
  

   p. 
  14 
  ; 
  P. 
  A. 
  Quenstedt, 
  Flozgeb. 
  Wiirttemb. 
  1843, 
  p. 
  244 
  (ed. 
  2, 
  

   1851, 
  p. 
  563), 
  and 
  Der 
  Jura, 
  1858, 
  p. 
  234). 
  

  

  An 
  indeterminable 
  portion 
  of 
  skull 
  and 
  anterior 
  vertebrae 
  from 
  

   the 
  Cretaceous 
  of 
  Pietraroja, 
  Benevento, 
  now 
  in 
  the 
  Geological 
  

   Museum 
  of 
  the 
  University 
  of 
  Naples, 
  bears 
  the 
  name 
  of 
  Asjpido- 
  

   rJiynchus 
  platycephalus 
  (0. 
  G. 
  Costa, 
  Atti 
  Accad. 
  Pontan. 
  vol. 
  viii. 
  

   1864, 
  pp. 
  62, 
  193, 
  pi. 
  ix. 
  fig. 
  8; 
  discussed 
  by 
  F. 
  Bassani, 
  Denkschr. 
  

   k. 
  Akad. 
  Wiss., 
  math.-naturw. 
  CI. 
  vol. 
  xlv. 
  1882, 
  p. 
  231). 
  The 
  

   same 
  specimen 
  was 
  previously 
  described 
  under 
  the 
  name 
  of 
  Dichelo- 
  

   spondylus 
  longirostris 
  by 
  0. 
  G. 
  Costa, 
  Ittiol. 
  Poss. 
  Ital. 
  (1856), 
  

   p. 
  18, 
  pi. 
  ii. 
  fig. 
  8. 
  

  

  Genus 
  BELONOSTOMUS, 
  Agassiz. 
  

  

  [Neues 
  Jahrb. 
  1834, 
  p. 
  388.] 
  

  

  Syn. 
  Ophirachis, 
  0. 
  G. 
  Costa, 
  Ittiol. 
  Foss. 
  Ital. 
  1856, 
  p. 
  13. 
  

  

  Snout 
  very 
  slender, 
  scarcely, 
  if 
  at 
  all, 
  produced 
  in 
  front 
  of 
  the 
  

   extremity 
  of 
  the 
  much-elongated 
  presymphysial 
  bone 
  ; 
  cheek- 
  

   plates 
  robust, 
  the 
  postorbitals 
  extending 
  to 
  the 
  anterior 
  border 
  of 
  

   the 
  preoperculum 
  ; 
  the 
  conical 
  teeth 
  irregular 
  in 
  size, 
  largest 
  on 
  

   the 
  hinder 
  part 
  of 
  the 
  preinaxillse 
  and 
  the 
  median 
  line 
  of 
  the 
  pre- 
  

   symphysial 
  bone, 
  obtuse 
  on 
  the 
  splenial, 
  and 
  reduced 
  to 
  a 
  fine 
  

   granulation 
  on 
  the 
  inner 
  face 
  of 
  the 
  ectopterygoid. 
  Ossified 
  vertebras 
  

   usually 
  pierced 
  by 
  a 
  remnant 
  of 
  the 
  notochord. 
  Pin-rays 
  distally 
  

   bifurcating 
  ; 
  fulcra 
  wanting 
  on 
  paired 
  fins, 
  rare 
  on 
  median 
  fins. 
  

   Pelvic 
  fins 
  situated 
  near 
  the 
  middle 
  of 
  the 
  trunk 
  ; 
  dorsal 
  and 
  anal 
  

   fins 
  short-based, 
  triangular, 
  remote 
  and 
  opposed 
  ; 
  caudal 
  fin 
  sym- 
  

   metrically 
  forked. 
  Scales 
  robust, 
  smooth 
  or 
  rugose 
  ; 
  in 
  three 
  

   deepened 
  series 
  on 
  the 
  flank 
  of 
  the 
  abdominal 
  region, 
  and 
  the 
  series 
  

   traversed 
  by 
  the 
  lateral 
  line 
  the 
  deepest 
  ; 
  dorsal 
  scales 
  between 
  the 
  

   flank-scales 
  aDd 
  the 
  median 
  ridge 
  in 
  two 
  series. 
  

  

  Belonostomus 
  sphyrsenoides, 
  

  

  1837. 
  Belanostomus 
  sphyrcznoides, 
  L. 
  Agassiz, 
  Bericht. 
  Versamml. 
  

  

  deutsch. 
  Naturf., 
  Jena, 
  1836, 
  p. 
  127 
  (name 
  only). 
  

   1837. 
  Belanostomus 
  brachysomus, 
  L. 
  Agassiz, 
  ibid. 
  p. 
  127 
  (name 
  only). 
  

  

  