﻿AND 
  OTHER 
  FAMILIES. 
  33 
  

  

  Cabinet 
  of 
  Professor 
  Kavenel, 
  Charleston, 
  S. 
  C. 
  

   Cabinet 
  of 
  P. 
  H. 
  Nicklin. 
  

   Cabinet 
  of 
  Professor 
  Vanuxem. 
  

   Diam. 
  *7, 
  Length 
  -9, 
  Breadth 
  1*5 
  inches. 
  

  

  Shell 
  widely 
  ovate, 
  oblique, 
  inequilateral, 
  subangulate 
  posteriorly, 
  

   slightly 
  inflated, 
  compressed 
  at 
  posterior 
  and 
  inferior 
  margins; 
  substance 
  

   of 
  the 
  shell 
  thick 
  and 
  white 
  anteriorly, 
  thin 
  and 
  iridescent 
  posteriorly 
  ; 
  

   ligament 
  short 
  and 
  thick; 
  epidermis 
  dark 
  brown 
  and 
  finely 
  wrinkled; 
  

   cardinal 
  tooth 
  short, 
  thick 
  and 
  deeply 
  divided 
  in 
  the 
  left 
  valve, 
  single 
  

   and 
  rising 
  from 
  a 
  pit 
  in 
  the 
  right 
  valve 
  ; 
  lateral 
  teeth 
  oblique, 
  straight 
  

   and 
  thick, 
  having 
  a 
  direction 
  over 
  the 
  lateral 
  tooth 
  ; 
  anterior 
  and 
  pos- 
  

   terior 
  cicatrices 
  both 
  distinct; 
  dorsal 
  cicatrices 
  situated 
  within 
  the 
  cavity 
  

   of 
  the 
  shell 
  on 
  the 
  plate 
  between 
  the 
  cardinal 
  and 
  lateral 
  teeth 
  ; 
  cavity 
  

   of 
  the 
  beaks 
  shallow 
  and 
  rounded 
  ; 
  nacre 
  white 
  in 
  the 
  anterior, 
  and 
  

   iridescent 
  in 
  the 
  posterior 
  portion. 
  

  

  Remarks. 
  — 
  This 
  shell, 
  which 
  I 
  owe 
  to 
  the 
  kindness 
  of 
  Professor 
  

   Ravenel, 
  has, 
  I 
  believe, 
  been 
  first 
  noticed 
  by 
  that 
  gentleman, 
  who, 
  sup- 
  

   posing 
  it 
  to 
  be 
  new, 
  sent 
  it 
  to 
  me 
  about 
  a 
  year 
  since. 
  It 
  diners 
  in 
  its 
  

   outline 
  from 
  any 
  of 
  our 
  eastern 
  species, 
  as 
  it 
  does 
  also 
  in 
  its 
  obliquity. 
  

   In 
  these 
  characters 
  it 
  most 
  resembles 
  the 
  U. 
  patulus 
  (nobis) 
  ; 
  it 
  is, 
  how- 
  

   ever, 
  more 
  dilated, 
  — 
  in 
  some 
  specimens 
  the 
  margin 
  being 
  subrotund. 
  

   The 
  only 
  specimens 
  obtained 
  by 
  Professor 
  Ravenel 
  being 
  imperfect, 
  

   and 
  much 
  eroded 
  at 
  the 
  beaks, 
  I 
  have 
  not 
  described 
  that 
  part, 
  leaving 
  

   it 
  for 
  future 
  observation. 
  There 
  are 
  no 
  rays 
  to 
  be 
  observed 
  on 
  the 
  

   specimens 
  I 
  have. 
  In 
  young 
  or 
  fine 
  specimens, 
  it 
  is 
  very 
  possible 
  they 
  

   may 
  exist. 
  

  

  Unio 
  Murchisonianus. 
  Plate 
  III. 
  fig. 
  6. 
  

  

  Testa 
  angulato-ellipticd, 
  transversa, 
  insequilaterali, 
  valvulis 
  tenuiculis 
  ; 
  natibus 
  

   perplicatis 
  ; 
  dentibus 
  cardinalibus 
  in 
  valvuld 
  utrdque 
  daplicibus, 
  lateralibus 
  rectis 
  ; 
  

   margaritd 
  pulchrd, 
  iridescente, 
  et 
  salmonis 
  colore 
  subtinctd. 
  

  

  Shell 
  narrow-elliptical, 
  transverse, 
  inequilateral; 
  valves 
  rather 
  thin; 
  beaks 
  much 
  

   VOL. 
  V. 
  1 
  

  

  