ERISMATUPvTNiE. 
pools  left  in  the  otherwise  dry  beds  of  streams.  It  is  extremely  difficult  to  shoot  them,  on  account  of  the  readines 
with  which  they  dive ; the  instant  the  trigger  is  drawn,  the  bird  is  under  water.” 
B.  lohata  (Shaw),  Shaw’s  Nat.  Misc.  pi.  255.,  PI.  col.  68.  — Biziura  novse  hollandife  Steph. ; Anas  carunculata  VieiU. 
Ekismatura  Pr.  Bonap.* 
Bill  nearly  as  long  as  the  head,  higher  at  the  base  than  broad,  the  culmen  suddenly  curved 
front  of  the  nostrils  and  then  depressed,  straight  and  the  sides  somewhat  dilated  near  the  tip,  ^ 
armed  with  a very  narrow  nail,  enlarged  and  hooked  beneath ; the  nostrils  oval  and  placed  ^ 
in  the  middle  of  the  bill.  Wings  short  and  concave,  with  the  first  two  quills  the  longest.  Tail  bBoj 
wedge-shaped,  and  composed  of  narrow  stiff  feathers.  Tarsi  half  the  length  of  the  middle  toe, 
compressed.  Toes  lengthened,  the  middle  and  outer  ones  of  equal  length,  and  the  three  anterior 
united  by  a full  web ; the  hind  toe  long,  elevated,  and  margined  by  a lobed  membrane ; the  c 
short,  curved,  and  acute. 
the 
The  species  are  scattered  in  various  parts  of  both  hemispheres.  They  are  peculiarly  aquatic  birds,  living  o 
large  sheets  of  saline  waters  and  rivers,  especially  those  that  run  into  the  sea.  In  such  jilaces,  they  are  generally  = 
small  societies  of  five  or  six  individuals,  and  mostly  apart  from  other  species  of  water  birds.  Their  bodies,  excep^^.^^ 
head  and  neck,  are  entirely  hidden  beneath  the  surface  of  the  water  when  swimming.  The  form  of  their  ijy 
makes  them  extremely  expert  in  diving,  when  seeking  for  molluscous  animals  and  fish,  on  which  they  pi® 
subsist.  The  nest  is  constructed  of  reeds  and  other  aquatic  plants,  in  such  a manner  that  it  floats  on  the  surface 
water. 
1 . E.  leucocephala  (Scop.)  Eyton,  Gould’s  B.  of  Eur.  pi.  — Anas 
mersa  Pall.  Reise  ii.  t.  11.,  Pall.  Zoogr.  t.  73.,  Hist,  de  I’Egypt.  Ois. 
pi.  10.  f.  2. 
2.  E.  rubida  (Wils.)  Bonap.,  Wils.  Amer.  Orn.  pi.  71.  f.  5,  6.  — 
Type  of  Gymnura  Nutt.  (1834.) 
3.  'Ei.ferruginea  Eyton,  Monogr.  Anat.  170. 
4.  E.  maccoa  (A.  Smith),  Eyton,  Monogr.  Anat.  l69-  P ‘ 
5.  E.  australis  (Gould),  Eyton,  Proc.  Z.  S.  1836.  85.  gpjnosa 
6.  E.  dominica  (Linn.)  Eyton,  PI.  enl.  968.  967-  ‘ 
Gmel.  0g. 
? 7.  E.  spinicauda  (VieilL)  Ency.  Meth.  356.,  Azat® 
— Anas  oxyura  Licht. 
Nesonetta. 
to 
Bill  shorter  than  the  head,  the  width  and  elevation  at  the  base  equal,  the  culmen  gradually  ; 
the  tip  which  is  armed  with  a moderate-sized  nail,  the  sides  comjiressed  and  of  equal  breadth  basoi 
the  lamellfB  of  the  interior  margins  of  the  upper  mandible  small  and  widely  set,  strongest  near 
the  nostrils  near  the  base,  lateral,  and  oval.  Wings  very  short  and  pointed,  with  the  second 
longest.  Tail  short  and  wedge-shaped,  with  the  end  of  the  stem  of  each  feather  bare  and  th® 
robust,  about  two  thirds  the  length  of  the  middle  toe.  Toes  strong,  with  the  outer  toe  shorter 
middle,  and  all  the  fore  toes  united  by  a full  web ; the  hind  toe  short,  elevated,  and  somewhat  o 
The  type  of  this  genus  is  peculiar  to  the  Auckland  Islands,  but  its  habits  are  at  present  unknown- 
N.  aucklandica.  — Mergus  australis  Homb.  Sf  Jacq.  in  Ann.  Sc.  Nat.  ser.  2.  xv.  p.  320.  ? 
* This  division  was  first  established  by  the  Prince  of  Canino  under  the  denomination  of  Owyura  {Ann.  Lyc.  Nat.  — 
1828,  p.  390.),  which,  having  been  previously  used,  was  changed  to  the  above  in  1832.  In  1 832,  Wagler  proposed  the  na 
in  1834,  Mr.  Nuttall  that  of  Gymnura  ; and  Mr.  Gould,  in  1836,  that  of  Undina. 
September,  1844. 
