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ANAS FULVIGULA 
not indistinguishable. Dr. Barbour tells me that he never noticed any difference, 
and Cory (1896) is of the same opinion. Harper (U.S. Biological Survey) speaks of 
the note as similar though perhaps not so loud as that of the Black Duck. Green, 
another Government collector, describes the note as slightly different from that of 
the Black Duck, and resembling hek-hek-hek-hek, quickly uttered. From the ob- 
servations which I myself made on birds in confinement and also in the field, I must 
confess that I never noticed anything characteristic in the voice. But these ducks 
are as a rule very silent, more so even than Mallards in the wild state. 
Food. A series of fifty-one stomachs of the Southern Black Duck was examined 
by McAtee (1918) and forty-eight were used in tabulating the percentages of various 
foods. These specimens were collected from November to April in the Everglades, 
and the river marshes of Florida, the coast marshes of Louisiana, and the coastal 
lakes and lagoons of Texas. The food is similar to that of the Black Duck but in- 
cludes even more animal matter. In fact 40% of the entire diet is of this nature. 
It thus consumes 15% more animal matter than the Black Duck and about 30% 
more than the Mallard. This is doubtless due to the fact that the habitat of the 
Southern Black Duck is subject to almost no cold weather so that animal life is 
abundant throughout the winter. Almost half of the vegetable food consists of 
various grasses, including the root-stocks, stems and leaves. Of the grass seeds con- 
sumed, waste rice gleaned from the rice-fields is most common. Probably in the 
summer the growing rice crop may be resorted to, at least these ducks are said to be 
destructive to growing rice. The seeds of smart-weed comprise 9.54% of the total 
diet. No fewer than 800 seeds of prickly smart-weeds {Polygonum sagittatum) were 
taken from one stomach. Seeds and tubers of sedges compose 6.34%, while seeds of 
water-lilies and coon-tail make up 3.11%. Seeds, stems and foliage of pond-weed 
and widgeon-grass are in the proportion of only 1.6%, while bayberries and seeds of 
buttonbush were also found. The principal animal food consists of shell-fish, which 
form nearly 27% of the whole diet and includes snails, some nearly one inch in 
diameter; insects, including dragon-fly nymphs, w'aterbugs, caddis larvae, beetles, 
and flies, even horse-fly larvae. Crustaceans comprise 2.77%, and small fishes 
2.54% of the w'hole diet. The stomach of a male taken by Harper (U.S. Biological 
Survey), in eastern Florida, contained 99% of smart- weed. 
Courtship and Nesting. The breeding season of this species is undoubtedly 
more irregular than in northern ducks and covers a greater period of time. A male 
killed by Harper (U.S. Biological Survey) on January 30 had large sex organs, and 
Dr. Thomas Barbour has heard of flappers being seen on Banana Creek, Indian 
River, early in March. Much earlier dates which I can only regard as very unusual 
were recorded by Mcllhenny (1916) and also in a letter to me. He reported nests 
