﻿* 
  

  

  ai 
  i 
  remark 
  of 
  the 
  

  

  which 
  Dearly 
  t<> 
  the 
  ventral 
  margin, 
  leaving 
  the 
  

  

  Idle 
  lob 
  a 
  prominent 
  sharp 
  ridge. 
  

  

  {'; 
  d 
  [aland 
  and 
  Menanda, 
  Albany 
  co. 
  

  

  • 
  » 
  li 
  i» 
  1 
  l> 
  i 
  ii 
  a 
  s 
  d 
  b 
  p 
  o 
  t 
  D 
  n 
  d 
  a 
  Bp. 
  n. 
  

   1. 
  . 
  

  

  I 
  . 
  < 
  k 
  Ulrica, 
  who 
  made 
  an 
  exhaustive 
  study 
  of 
  these 
  forma 
  and 
  

   ribed 
  the 
  sp< 
  n 
  o 
  b 
  o 
  1 
  b 
  i 
  n 
  a 
  occurring 
  in 
  the 
  Cin- 
  

  

  cinnati 
  beds, 
  rep 
  v 
  species 
  from 
  the 
  Trenton 
  1. 
  

  

  - 
  >ta 
  (49:674, 
  675). 
  To 
  I 
  a 
  idded 
  a 
  new 
  e 
  

  

  fonnd 
  in 
  the 
  mid 
  entonshal 
  Schuyler 
  (station 
  2 
  

  

  Valves 
  Bhortly 
  Bubovate, 
  ajly 
  convex, 
  dorsal 
  margin 
  nearly 
  

  

  entral 
  pari 
  approaching 
  a 
  Bemicircle 
  in 
  outline: 
  bu! 
  

   wide 
  and 
  deep, 
  beginning 
  near 
  the 
  middle 
  of 
  the 
  dorsal 
  margin, 
  

   obli< 
  _ 
  backward 
  in-low, 
  dividing 
  the 
  carapace 
  into 
  two 
  

  

  Bubequal 
  lobes, 
  which 
  are 
  broadly 
  connected 
  in 
  the 
  ventral 
  

   <>n. 
  the 
  posterior 
  lobe 
  distinctly 
  rounded 
  and 
  inclined 
  to 
  be 
  a 
  

   little 
  1. 
  nan 
  the 
  anterior; 
  both 
  lobes 
  equally 
  convex, 
  with 
  a 
  

  

  anteriorly 
  and 
  posteriorly; 
  surface 
  minutely 
  

   granuli 
  

  

  Dran 
  - 
  s. 
  Length 
  .56 
  nun. 
  hight 
  3R 
  mm. 
  thickness 
  .17 
  mm: 
  

   length 
  of 
  a 
  smaller 
  carapace, 
  . 
  i 
  v 
  mm. 
  hight 
  .34 
  mm, 
  thickness 
  .20 
  

   mm. 
  

   These 
  minute 
  valves 
  are 
  undoubtedly 
  closely 
  related 
  t<» 
  the 
  two 
  

   n 
  t 
  • 
  .11 
  - 
  s 
  of 
  tenobolbina 
  described 
  by 
  Ulri 
  

   They 
  fully 
  agree 
  with 
  them 
  in 
  the 
  presence 
  of 
  only 
  one 
  sulcus 
  

   which 
  _ 
  y 
  curved 
  and 
  of 
  two 
  bordered 
  lobes; 
  bul 
  they 
  

  

  dit 
  m 
  the 
  one 
  fulcra 
  in 
  having 
  the 
  posterior 
  

  

  bulb 
  already 
  further 
  advance 
  d, 
  and 
  from 
  the 
  other 
  (Ct 
  cr 
  

  

  development 
  of 
  the 
  herder 
  and 
  the 
  Bhorter, 
  more 
  

  

  rotund 
  outline. 
  Ctenobolbina 
  Bubrotunda 
  ditfers 
  

  

  ii 
  Ct. 
  d 
  ii 
  r 
  - 
  A. 
  Miller 
  sp. 
  ' 
  quart, 
  four. 
  %d. 
  L874. 
  

  

  l 
  •_• 
  - 
  • 
  nil 
  from 
  the 
  "Hudson 
  river 
  group" 
  of 
  Cincin- 
  

  

  i 
  in 
  h- 
  _ 
  latively 
  much 
  big 
  ad 
  having 
  the 
  sulcus 
  n 
  

  

  medially 
  located. 
  

  

  