21 
was first given to it, according to Stephens, in Shaw’s Zoology, by 
Leach, in his MSS., and was afterwards published by Mr. Stephens 
in the above work. 
GENUS Ill. ERISMATURA. 
Ext. Cuar. Pedes digitis posterioribus lobatis, externis mediis 
yix equantibus.  TZibie plumate.  ostrum validum, aut mediocre, 
prope apicem latissimum. Mandibule unguiculate. Nares ovales, 
parve, in medio rostri versus culminem posite. Cauda rotundata, 
rectricibus rigidis. Ale remigibus paululum incurvatis. 
Ext. Cuar. fet with the posterior toes lobated, the outer one 
scarcely equal to the inner. Thighs feathered. Bill moderate, 
broadest near the tip. Mandibles furnished with nails. Nostrits oval, 
small, placed in the middle of the bill towards the culmen. Tail 
‘rounded, with the quills stiff. Wings with the quills a little incurved. 
~ Anas. Linn. 
Oxyura. Bonap. 
ERIsMATuRA. Bonap. 
Unpina. Gould. 
Gymnura. Nuttall. 
Type. LHrismatura rubida. 
The genus Oxyura was first instituted by the Prince of Musignano, 
for the reception of Anas rubida, Wils. Mr. Gorler having over- ~ 
looked it, formed his genus Undina, or Anas Leucocephala, Linn., a 
bird of the same conformation. Mr. Nuttall having discovered that 
the name of Oxyura had been before used for a genus of creepers, 
substituted that of Gymnura for it. The Prince of Musignano had, 
however, in the appendix to the same work in which he named the 
~ genus Oxyura, also called it Hrismatura, which name will stand, that. 
of Oxyura having been before employed for another genus. 
SUB FAM. VI. MERGINA. 
Ext. Cuar. fostrum mediocre, ad apicem angustatum acumina- 
tum et dentibus ad latera instructum. Digiti posteriores lobati. 
Ext. Cuar. Sill moderate, narrowed to the point, acuminate, 
and at the sides armed with teeth. Posterior Toes lobated. 
Type. Mergus. 
