Order  VIII.  AN  SERES 
Family  I.  Anatid^:. 
The  fifth  Subfamily, 
ANATINiE,  or  River  Ducks, 
have  the  Bill  lengthened,  more  or  less  broad,  depressed  towards  the  tip,  which  is  furnished  with  a 
hard  nail,  and  the  inner  portion  of  the  lateral  margins  more  or  less  lamellated  ;  the  Tarsi  compressed, 
and  generally  the  length  of  the  inner  toe  ;  the  hind  Toe  lengthened,  and  slightly  bordered  with  a 
membranous  lobe  from  the  base  to  the  tip. 
Dendrocygna  Swains.* 
Bill  long,  higher  at  the  base  than  broad,  with  the  culmen  sloping  to  the  tip,  which  is  armed  with  a 
strong  broad  nail,  and  the  lateral  margins  straight ;  the  lamella}  of  the  upper  mandible  advancing  below 
the  lateral  margins,  slender,  and  set  widely  apart  ;  the  nostrils  large,  oval,  and  placed  near  the  base 
and  culmen.  Wings  short  and  rounded,  with  the  second,  third,  and  fourth  quills  the  longest  ;  the  first 
quill  with  a  deep  notch  in  the  middle,  and  the  secondaries  nearly  as  long  as  the  quills.  Tail  moderate, 
and  rounded  at  its  end.  Tarsi  slightly  shorter  than  the  middle  toe,  robust.  Toes  long,  the  lateral  ones 
united  to  the  middle  one  by  an  indentated  membrane;  and  the  hind  toe  very  long,  elevated,  and  simple. 
These  birds  are  migratory,  residing  in  Asia,  Africa,  the  West  Indies,  South  America,  and  Australia  ;  and  they  are 
found  in  troops  on  the  fresh-water  rivers  and  ponds,  seeking  their  food,  which  consists  of  vegetable  matter.  During 
the  warm  part  of  the  day  and  at  night  they  roost  on  the  trees. 
1.  D.  arcuatu  (Cuv.)  Swains.  Horsf.  Zool.  Res.  pi.  —  Anas  .  5.  D.  viduata  (Linn.)  Eyton,  Penn.  Gen.  Birds,  pi.  13.,  PI.  enl. 
javanica  Horsf. ;  Mareea  awsuree  Sykes.  808. 
2.  D.  major  Jerd.  Madr.  Journ.  1840.  218.  6.  D.  virgata  (Pr.  Max.). 
3.  D.  autumnnlis  (Linn.)  Eyton,  PI.  enl.  826.,  Edwards's  Birds,  |  7.  D.  Eyton i  (Gould),  B.  of  Austr.pl.  —  Type  of  Leptotarsis 
pi.  149.  J  Gould  (1838). 
4.  D.  arborea  (Linn.)  Eyton,  PI.  enl.  804.,  Edwards's  Birds,  pi. 
193. 
Tadorna  Leach.  + 
Bill  shorter  than,  or  as  long  as,  the  head,  higher  at  the  base  than  broad,  with  the  culmen  (furnished 
at  times  with  a  round  tubercle)  concave  in  the  middle,  depressed,  and  curved  upwards  at  the  tip, 
which  is  suddenly  hooked  with  a  strong  narrow  nail  ;  the  basal  part  of  the  lateral  margin  nearly  straight 
*  Established  by  Mr.  Swainson  (Class:  of  Birds,  ii.  36'5.)  in  1S37.  Wagler's  generic  name  of  Dindronessa  was  proposed  in  1832,  but 
that  name  had  been  previously  employed  by  Mr.  Swainson.    Mr.  Gould's  genus  Leptotarsis  is  coequal  with  them. 
t  Proposedby  Leach  previously  to  1822,  when  Dr.  Fleming  introduced  it  into  the  Phil,  of  Zool.  p.  260.  In  1840,  Count  Keyserling  and 
Prof.  Blasius  used  in  its  place  Vulpanser. 
