﻿AND 
  OTHER 
  FAMILIES. 
  45 
  

  

  Anodonta 
  Ferussaciana. 
  Plate 
  VI. 
  fig. 
  15. 
  

  

  Testa 
  subcylindraced, 
  insequilaterali, 
  inflatd 
  ; 
  margine 
  dorsali 
  sub 
  natium 
  

   apices 
  curvd 
  ; 
  valvulis 
  tenuibus 
  ; 
  epidermidefulgidd, 
  obsolete 
  radiald, 
  olivae 
  colorem 
  

   tenebrosum 
  habente 
  ; 
  natibus 
  prominulis, 
  binis 
  ternisve 
  undulis 
  exiguis 
  ad 
  apices 
  ; 
  

   cicatricibus 
  conspicuis 
  ; 
  margaritd 
  cceruleoalbd 
  et 
  iridescente. 
  

  

  Shell 
  subcylindrical, 
  inequilateral, 
  inflated 
  ; 
  dorsal 
  margin 
  curved 
  immediately 
  

   under 
  the 
  point 
  of 
  the 
  beak 
  ; 
  valves 
  thin 
  ; 
  epidermis 
  dark 
  olive, 
  shining, 
  with 
  obsolete 
  

   rays 
  ; 
  beaks 
  somewhat 
  prominent 
  with 
  two 
  or 
  three 
  small 
  undulations 
  at 
  tip 
  ; 
  cicatrices 
  

   perceptible 
  ; 
  nacre 
  bluish 
  white 
  and 
  iridescent. 
  

  

  Hab. 
  Ohio 
  Riyer, 
  near 
  Cincinnati. 
  T. 
  G. 
  Lea. 
  

  

  My 
  Cabinet. 
  

   Cabinet 
  of 
  the 
  Academy 
  of 
  Natural 
  Sciences 
  of 
  Philadelphia. 
  

   Cabinet 
  of 
  Mr 
  Nicklin. 
  

   Cabinet 
  of 
  Professor 
  Vanuxem. 
  

   Cabinet 
  of 
  the 
  American 
  Philosophical 
  Society 
  of 
  Philadelphia. 
  

   Diam. 
  1*4, 
  Length 
  1*8, 
  Breadth 
  3*5 
  inches. 
  

  

  Shell 
  subcylindrical, 
  inequilateral, 
  much 
  inflated, 
  more 
  angular 
  

   behind 
  than 
  before; 
  dorsal 
  margin 
  curved 
  immediately 
  under 
  the 
  

   point 
  of 
  the 
  beak 
  ; 
  basal 
  margin 
  disposed 
  to 
  be 
  emarginate 
  ; 
  substance 
  

   of 
  the 
  shell 
  thin 
  ; 
  epidermis 
  dark 
  olive, 
  shining, 
  with 
  numerous 
  obso- 
  

   lete 
  rays, 
  near 
  the 
  beaks 
  lighter 
  and 
  destitute 
  of 
  rays 
  ; 
  ligament 
  rather 
  

   short 
  and 
  thin 
  ; 
  beaks 
  somewhat 
  prominent 
  with 
  two 
  or 
  three 
  small 
  

   undulations 
  at 
  tip 
  ; 
  cicatrices 
  perceptible 
  ; 
  cavity 
  of 
  the 
  beaks 
  shallow 
  ; 
  

   cavity 
  of 
  the 
  disk 
  deep 
  and 
  rounded 
  ; 
  nacre 
  bluish 
  white 
  and 
  iridescent. 
  

  

  Remarks. 
  — 
  This 
  species 
  was 
  received 
  with 
  the 
  A. 
  incerta, 
  here- 
  

   in 
  described, 
  from 
  the 
  Ohio 
  river. 
  It 
  differs 
  from 
  that 
  species 
  in 
  

   having 
  prominent 
  beaks, 
  in 
  being 
  more 
  cylindrical, 
  in 
  its 
  dark 
  colour, 
  

   and 
  in 
  the 
  curve 
  which 
  exists 
  immediately 
  under 
  the 
  beaks, 
  in 
  which 
  

   it 
  resembles 
  the 
  A. 
  areolus 
  (Swainson). 
  In 
  the 
  latter 
  this 
  curve 
  is 
  so 
  

   strong 
  and 
  thick 
  as 
  to 
  resemble 
  an 
  incipient 
  tooth. 
  In 
  young 
  speci- 
  

   mens 
  the 
  epidermis 
  is 
  more 
  on 
  the 
  yellow, 
  and 
  the 
  rays 
  greenish 
  and 
  

   bright.* 
  

  

  * 
  Since 
  the 
  above 
  description 
  was 
  made 
  and 
  the 
  figure 
  printed, 
  I 
  am 
  in 
  possession 
  of 
  sev- 
  

   eral 
  specimens 
  from 
  Illinois, 
  beautifully 
  and 
  very 
  distinctly 
  rayed. 
  

   VOL. 
  V 
  M 
  

  

  