﻿PLATE 
  III. 
  

  

  Gomphoceras 
  mitriformis, 
  sp. 
  nov. 
  

  

  Fig. 
  1. 
  — 
  The 
  original 
  specimen, 
  which 
  is 
  in 
  a 
  somewhat 
  macerated 
  

   condition, 
  but 
  its 
  outline 
  is 
  apparently 
  entire 
  and 
  undisturbed. 
  

   Marcellus 
  shales. 
  Chapinville, 
  JV. 
  Y. 
  

  

  Lunulicardmm 
  ? 
  lineolatum, 
  sp. 
  nov. 
  

  

  Fig. 
  2. 
  — 
  A 
  left 
  valve 
  enlarged 
  to 
  three 
  diameters, 
  showing 
  the 
  sharp 
  

   elevated 
  radial 
  lines 
  covering 
  the 
  concentric 
  lines 
  of 
  growth. 
  The 
  

   posterior 
  extension 
  of 
  the 
  hinge 
  has 
  been 
  represented 
  as 
  too 
  straight 
  

   and 
  abrupt, 
  there 
  actually 
  being 
  in 
  this 
  portion 
  of 
  the 
  cardinal 
  region 
  

   a 
  convex 
  curvature 
  of 
  the 
  valve 
  to 
  the 
  hinge. 
  

  

  Upper 
  layers 
  of 
  the 
  Hamilton 
  shales, 
  beticeen 
  225 
  and 
  350 
  feet 
  in 
  

   the 
  Livonia 
  shaft. 
  

  

  Ceratostigma 
  papillata, 
  sp. 
  nov. 
  

  

  Fig. 
  3. 
  — 
  A 
  natural 
  size 
  view 
  of 
  the 
  longest 
  specimen. 
  

  

  Fig. 
  4. 
  — 
  The 
  same 
  enlarged 
  to 
  three 
  diameters 
  to 
  show 
  the 
  struc- 
  

   ture 
  of 
  the 
  surface. 
  On 
  parts 
  ofthis 
  specimen 
  the 
  thin 
  layer 
  of 
  the 
  

   substance 
  of 
  the 
  fossil 
  has 
  been 
  removed 
  and 
  exposes 
  an 
  impression 
  of 
  

   the 
  inner 
  side. 
  The 
  outermost 
  chitinous 
  coat 
  of 
  the 
  species 
  is 
  not 
  here 
  

   preserved. 
  

  

  Fig. 
  5. 
  — 
  An 
  external 
  cast 
  of 
  a 
  portion 
  of 
  a 
  zoary 
  enlarged 
  to 
  five 
  

  

  diameters. 
  

  

  379 
  

  

  