﻿410 
  ACTINOPTERFGII. 
  

  

  with 
  a 
  transverse 
  diameter 
  of 
  # 
  035 
  at 
  its 
  base 
  where 
  the 
  vomerine 
  

   teeth 
  are 
  implanted, 
  but 
  more 
  slender 
  than 
  the 
  rostrum 
  of 
  P. 
  nitida 
  ; 
  

   transverse 
  section 
  a 
  depressed 
  oval 
  throughout 
  ; 
  surface 
  ornamented 
  

   with 
  conspicuous 
  longitudinal 
  rugae, 
  in 
  part 
  reticulated. 
  

  

  Form. 
  Sf 
  Log. 
  Upper 
  Cretaceous 
  (Niobrara 
  Group) 
  : 
  Kansas, 
  

   U.S.A. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  The 
  following 
  specimens 
  of 
  Protosphyrcena 
  are 
  not 
  specifically 
  

   determined 
  : 
  — 
  

  

  40395. 
  Imperfect, 
  abraded 
  rostrum, 
  much 
  elongated 
  and 
  either 
  

   depressed 
  or 
  compressed 
  ; 
  Chalk, 
  Burham, 
  Kent. 
  

  

  Purchased, 
  1867. 
  

  

  47291. 
  Imperfect, 
  crushed 
  rostrum, 
  much 
  elongated 
  and 
  depressed, 
  

   exhibiting 
  remains 
  of 
  an 
  external 
  ornament 
  of 
  fine 
  longi- 
  

   tudinal 
  rugae 
  ; 
  Grey 
  Chalk, 
  Dover. 
  Gardner 
  Coll. 
  

  

  P. 
  7243-44. 
  Nine 
  jaw-fragments 
  ; 
  Cambridge 
  Greensand, 
  Cam- 
  

   bridge. 
  Jesson 
  Coll. 
  

  

  P. 
  1796. 
  Fragment 
  of 
  premaxilla 
  ; 
  Gault, 
  Barnwell, 
  near 
  Cam- 
  

   bridge. 
  Egerton 
  Coll. 
  

  

  30258, 
  35131, 
  35437, 
  40356. 
  Teeth 
  ; 
  Cambridge 
  Greensand. 
  

  

  Purchased, 
  1855, 
  1859, 
  1867. 
  

  

  47961. 
  Five 
  teeth 
  ; 
  Cambridge 
  Greensand. 
  

  

  Presented 
  by 
  Hon. 
  Robert 
  Marsham, 
  1877. 
  

  

  P. 
  7245. 
  Three 
  imperfect 
  large 
  teeth 
  ; 
  Cambridge 
  Greensand. 
  

  

  Jesson 
  Coll. 
  

  

  32392. 
  Tooth 
  ; 
  Upper 
  Greensand, 
  Kilmerton, 
  Isle 
  of 
  Wight. 
  

  

  Purchased, 
  1857. 
  

  

  35675. 
  Tooth 
  ; 
  Eed 
  Chalk, 
  Speeton, 
  Yorkshire. 
  Bean 
  Coll. 
  

  

  47225. 
  Ten 
  teeth 
  ; 
  Gault, 
  Folkestone. 
  Gardner 
  Coll. 
  

  

  36111. 
  Tooth 
  ; 
  Grey 
  Chalk, 
  Dover. 
  Purchased, 
  1861. 
  

  

  P. 
  406. 
  Tooth 
  ; 
  Grey 
  Chalk, 
  Dover. 
  

  

  Presented 
  by 
  the 
  Earl 
  of 
  Ducie, 
  1881. 
  

  

  47247. 
  Three 
  teeth 
  ; 
  Chalk 
  Marl, 
  Dover. 
  Gardner 
  Coll. 
  

  

  