A Hybrid Duck. — After ten years of hunting for real wild hybrids, 
the writer has finally succeeded in securing a drake which he regards as 
an even mixture of Mallard and Northern Black Duck. The bird was 
shot by the writer about a year ago, and he has waited some time for the 
experience to be repeated — as often happens after one has once succeeded 
in finding a bird or flower new to him — but I have caught no mate for 
my drake. 
Several thousands of ducks have been examined in the hope, not merely 
of finding rare ducks in the market or in the strings of gunners, but 
especially for indications of a crossed breed. Often I have found ‘ blue 
bills’ which could be assigned only with great difficulty to the species 
Aythya affinis or to A. marila. Especially was this true of females. 
Measurements have been found quite unreliable in deciding these cases, 
for it is a common thing to find a male of A. affinis which is up to the 
smaller measurements of A. marila , and often the flank markings are so 
indefinite, and the head iridescence also, that no one could say with pre¬ 
cision what the bird was. Hybrids in these races are practically indefin¬ 
able. 
But between the Mallard and Black Duck we expected to find crosses, 
and also to be able to distinguish them with certainty. While it has been 
a common experience to come across Black Ducks which show traces of 
Mallard blood, as was Mr. Brewster’s experience, I have been unable to 
find any Mallard which could be said to bear traces of a Black Duck in¬ 
fusion. It is true that these latter forms would be harder to distinguish, 
but the young drakes and females were carefully examined with the possi¬ 
bilities fully in mind. 
These traces of Mallard blood we have found most common in the form 
recently described by Mr. Brewster as Anas obscura rubripes — birds 
which we have habitually called “Winter” or “Big” Black Ducks in this 
vicinity. 
The hybrid here under notice exhibits strong Black Duck characters on 
the head, neck and back. The pattern and dusky shade of the Black Duck 
are also shown on all portions of the plumage, even where the Mallard 
affinities are strongest. Mallard blood shows strongest in the white frame 
of the speculum which is about one-half the typical width of white seen 
in the Mallard, in the light shade and wavy cross vermiculations of the 
scapulars, flanks and belly, in the blackish upper and under tail-coverts, 
and in the green of the nape and sides of the crown. 
This specimen was in prime physical condition, an adult male with the ■ 
testes unusually well developed considering the time of year. — Elon 
Howard Eaton, Rochester , N. Y. 
Auk, XX, Jan., 1903, p- V- 
C aJM C 
Auk, XX.11, Apr,, 1906, p , 
V_ajWt/') 
