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in the rest of the family. The genus Wicropterus has, on the other 
hand, a trachea very nearly resembling that of the true land duck. 
We prefer taking the genus Anas, as at present restricted, for the 
type of this sub-family, instead of Rhynchaspis, as proposed by Mr. 
‘Swainson, regarding that form and the nearly allied one of 
Malacorhynchus rather as ultra than typical, and not so well suited 
to what may be termed the true habit of the sub-family as that we 
~ have chosen. 
GENUS I. TADORNA. 
Ext. Cuar. Pedes digitis posterioribus non lobatis, unguibus 
robustis armatis. TZarsirobustietlongi. Rostrum mediocre validum 
recurvatum. amelie vix elongate. Nares ovales, magne, in 
dimidio basali rostri posite. Cauda rotundata. 
Ext. Cuar. Feet with the posterior toes not lobated, armed with 
thick claws. TYarsi thick and long. ill moderately strong. Lamelle 
scarcely elongated. Nostrils oval, large, placed in the basal half of 
the bill. Zail rounded. 
Anas. Linn., Gmel., Lath. 
_ Taporna. Leach., Flem., Steph. 
Tyre. Tadorna Belloni. 
Affinities. The common Sheldrake approaches near in external 
character to the following genus. Nothing being known of the 
anatomy of that genus, we cannot trace the affinity farther. To the 
Anserine it also approaches in its osteology and general habit, par- 
ticularly to the genus Chenalopex. 
GENUS II. CASARKA. 
Ext. Cuar. Aostrum mediocre lateribus parallelibus non recur- 
vatum. JVares subovales, culminem versus posite. Lamelle elongate. 
Pedes robusti, digiti unguibus magnis armati. 
Ext. Cuar. Sill moderate, with the sides parallel, not recurved. 
Nostrils suboval, placed near the culmen. JLamelle elongated. Feet — 
robust, the toes armed with large claws. 
Anas. JLinn., Lath. 
Taporna. Selby. 
CasarKA. Bonap. 
Type. Casarka rutila. 
Affinity. This genus may be distinguished from Tadorna, to 
which it is closely allied, by the straighter and much shorter bill. 
