ELEVEN 1 'l PORT \ \ T \v 1 1 D DICK FOODS. 17 
taken a1 the same time and place was 84 per cenl wigeon-grass; and 
the stomach of a redhead Contained aboul 5,120 seeds. 
Most of the duck stomachs received by the Biologica] Survey from 
South Island, South. Carolina, have contained wigeon-grass. It com- 
posed^ per cenl of the food of 3 blue-winged teals collected therein 
March, mid 27 per cent of thai of 8 gadwells obtained in February 
and March. In Currituck Sound, North Carolina, wigeon-grass grows 
among too great a profusion of other valuable duck foods to have the 
importance attained in less favored localities; nevertheless, it is a plant 
of considerable value. Practically 10 per cent of the food of 35 big 
bluebills collected there in November was composed of wigeon-grass, 
as was about the same proportion of the diet of 70 little bluebills. 
At Back Bay. Virginia, 17 per cent of the food of 9 pintails collected 
in February consisted of wigeon-grass, and at Virginia City, Va. 7 16 
per cent of the food of 14 mallards taken in January was of the same 
composition. 
Other ducks found feeding on wigeon-grass are the Florida duck, 
black duck, green-winged and cinnamon teals, spoonbill, canvasback, 
rin Li-neck, bufflehead, old squaw, ruddy duck, surf scoter, and hooded 
merganser. 
DESCRIPTION OF PLANT. 
Wigeon-grass (Ruppia maritima) is similar in habit to sago pond- 
weed or foxtail. 1 Both have long, slender, filamentous leaves on 
widely spreading, much-branched stems. In wigeon-grass the basal 
parts of many of the leaves are enlarged (fig. 15), and this, upon 
close inspection, gives the plant quite a different appearance from 
sago pondweed. The seeds of sago pondweed are compactly grouped 
on a central axis, while those of wigeon-grass are borne singly on 
rather long stalks which radiate from the top of the fruiting peduncle 
(fig. 16). The latter organ usually is spirally coiled in wigeon-grass; 
in sago pondweed it never has more than a simple curve. The 
rootstock of wigeon-grass is tougher than that of sago pondweed, 
more frequently jointed, and often angled at the joints. There are 
no tubers. The seeds are black, rounded triangular in outline, with 
a small pit on each side near the apex, and on one edge an oblong lid 
which is forced out during germination. Pondweed seeds have a simi- 
lar lid, but are usually larger than those of wigeon-grass, never black, 
and lack the apical pits. 
Wigeon-grass is usually referred to in books as sea- or ditch-grass; 
it is also called tassel-grass, tassel-weed, tassel-pondweed, nigger-wool, 
puldoo-grass, and peter-grass. The last two names are compounded 
from terms by which the coot is known in southern States, and indi- 
cate that wigeon-grass is highly relished by that bird. 
1 Described in Biological Survey Circular No. 81, pp. 12-16. 
