﻿AND 
  OTHER 
  FAMILIES. 
  39 
  

  

  My 
  Cabinet. 
  

   Cabinet 
  of 
  the 
  Academy 
  of 
  Natural 
  Sciences 
  of 
  Philadelphia. 
  

   Cabinet 
  of 
  Mr 
  Stewart. 
  

   Cabinet 
  of 
  Mr 
  Hyde. 
  

   Diam. 
  -9, 
  Length 
  1 
  # 
  4, 
  Breadth 
  2*7 
  inches. 
  

  

  Shell 
  trapezoidal, 
  very 
  inequilateral, 
  transverse, 
  compressed, 
  angular 
  

   behind 
  ; 
  substance 
  of 
  the 
  shell 
  rather 
  thin 
  ; 
  umbonial 
  slope 
  subcarinate 
  ; 
  

   beaks 
  slightly 
  prominent, 
  placed 
  near 
  the 
  anterior 
  margin 
  and 
  concen- 
  

   trically 
  wrinkled 
  ; 
  carina 
  much 
  elevated 
  ; 
  ligament 
  long, 
  narrow 
  and 
  

   nearly 
  straight 
  ; 
  epidermis 
  dark 
  brown, 
  wrinkled 
  and 
  sometimes 
  ob- 
  

   scurely 
  rayed 
  ; 
  cardinal 
  teeth 
  oblique 
  and 
  double 
  in 
  both 
  valves 
  ; 
  lateral 
  

   teeth 
  nearly 
  straight 
  and 
  lamelliform 
  ; 
  anterior 
  cicatrices 
  distinct, 
  pos- 
  

   terior 
  cicatrices 
  confluent 
  ; 
  dorsal 
  cicatrices 
  situated 
  in 
  the 
  centre 
  of 
  

   the 
  cavity 
  of 
  the 
  beaks 
  ; 
  cavity 
  of 
  the 
  beaks 
  shallow 
  : 
  nacre 
  purple 
  and 
  

   iridescent. 
  

  

  Remarks. 
  — 
  This 
  interesting 
  species 
  is 
  one 
  of 
  the 
  collection 
  made 
  by 
  

   Mr 
  Stewart 
  in 
  the 
  Bayou 
  Teche. 
  It 
  is 
  a 
  very 
  distinct 
  and 
  beautiful 
  

   species. 
  Its 
  form 
  is 
  more 
  like 
  a 
  trapezium 
  than 
  that 
  of 
  any 
  other 
  spe- 
  

   cies 
  with 
  which 
  I 
  am 
  acquainted. 
  It 
  resembles 
  most 
  the 
  U. 
  compla- 
  

   natus 
  (Soland.). 
  It 
  differs 
  from 
  it, 
  however, 
  in 
  its 
  remarkable 
  outline, 
  

   in 
  its 
  teeth, 
  in 
  the 
  concentric 
  wrinkles 
  of 
  the 
  beaks, 
  and 
  in 
  the 
  beaks 
  

   being 
  placed 
  nearer 
  to 
  the 
  anterior 
  margin. 
  The 
  angle 
  of 
  the 
  poste- 
  

   rior 
  margin 
  is 
  also 
  more 
  acute. 
  In 
  the 
  deep 
  brown 
  colour 
  of 
  the 
  epi- 
  

   dermis 
  and 
  in 
  outline 
  of 
  the 
  margin 
  it 
  approaches 
  the 
  U. 
  obesus 
  (nobis). 
  

   It 
  is, 
  however, 
  much 
  less 
  inflated. 
  

  

  Unio 
  Taitianus. 
  Plate 
  IV. 
  fig. 
  11. 
  

  

  Testa 
  subtriangulari, 
  obliqud 
  crassdque 
  ; 
  valvulis 
  antice 
  crassioribus 
  ; 
  dentibus 
  

   cardinalibus 
  grandibus 
  et 
  elevatis, 
  lateralibus 
  crassis 
  et 
  subcurvis 
  ; 
  margaritd 
  

   alba. 
  

  

  Shell 
  subtriangular, 
  thick 
  and 
  oblique; 
  valves 
  thicker 
  anteriorly 
  ; 
  cardinal 
  teeth 
  large 
  

   and 
  elevated 
  ; 
  lateral 
  teeth 
  thick 
  and 
  slightly 
  curved 
  ; 
  nacre 
  pearly 
  white. 
  

  

  