﻿178 
  Twenty-eighth 
  Kepokt 
  on" 
  the 
  State 
  Museum. 
  

  

  CYRTOLITES 
  Conrad. 
  

  

  Cyrtolites 
  slntjosus. 
  

  

  Plate 
  30, 
  Figs. 
  16-18. 
  

  

  Cyrtolites 
  sinuosus 
  Hall. 
  Doc. 
  Edit. 
  28th 
  Rep. 
  St. 
  Mus. 
  Nat. 
  Hist. 
  Explanation 
  

   of 
  pi. 
  30, 
  figs. 
  16-18. 
  1876. 
  

  

  Shell 
  convolute, 
  volutions 
  in 
  the 
  same 
  plane, 
  contiguous. 
  

   Body 
  of 
  the 
  shell 
  strongly 
  lobed, 
  the 
  dorsum 
  being 
  separated 
  

   from 
  the 
  lateral 
  portions 
  of 
  the 
  shell 
  by 
  a 
  distinct 
  groove 
  or 
  

   sinus 
  on 
  each 
  side. 
  Aperture 
  elongate, 
  subquadrate, 
  auri- 
  

   culate 
  at 
  the 
  sides, 
  and 
  the 
  peristome 
  deeply 
  sinuated 
  in 
  

   front. 
  

  

  The 
  specimens 
  of 
  this 
  species 
  are 
  casts 
  of 
  the 
  interior, 
  and 
  

   the 
  surface- 
  markings 
  are 
  unknown. 
  This 
  form 
  may 
  be 
  com- 
  

   pared 
  with 
  Bucania 
  trilobata, 
  of 
  the 
  Medina 
  Sandstone 
  and 
  

   Clinton 
  group, 
  but 
  it 
  is 
  less 
  gibbous, 
  more 
  abruptly 
  trilobate, 
  

   and 
  is 
  marked 
  by 
  a 
  deep 
  abrupt 
  sinus 
  in 
  the 
  anterior 
  margin 
  

   of 
  the 
  peristome 
  — 
  a 
  feature 
  not 
  known 
  in 
  that 
  species. 
  

  

  