FOOD HABITS OF SHOAL-WATER DUCKS. 45 
VINE FAMILY (VITACEAE), 0.82 PER CENT. 
The estimated average percentage, 0.82, of the remains of grapes 
actually found in the wood duck stomachs, undoubtedly is much 
less than the true proportion of grapes consumed, for the skins, 
pulp, and juice are very quickly digested, leaving nothing but the 
seeds, or much more commonly, fragments of seeds, to show that 
grapes had been eaten. It is probable that most of these grapes 
are picked up from the ground in the woods, though some may be 
taken from the vines. Traces of grapes (always in the form of seeds 
or seed-fragments) were present in 141 of the wood duck stomachs. 
OLIVE FAMILY (OLEACEAE), 0.72 PER CENT. 
Two wood ducks had eaten seeds of ash (Fraxinus americana and 
other species), The remainder of the food from this family of plants 
consisted of the seeds of swamp privet (Adela acuminata), which 
Were present in 31 stomachs. This is a favorite food for wild ducks 
in some southern localities, according to the testimony of numerous 
hunters. ‘‘ Wood ducks in particular are said to feed extensively 
upon its seeds. Weeks before other species of ducks arrive these 
birds are abundant in the country where swamp privet grows and 
are said to consume most of the crop of seeds, leaving little for other 
ducks.” © The plant is a shrub or small tree, and the seed, which 
has a fibrous, ridged coat, is inclosed in a watery blue berry from 
one-half to three-fourths of an inch in length. These berries ripen 
in May and June and fall into the water; many of them are picked 
up from the bottom by the ducks later in the season. The swamp 
privet grows in the same kind of localities as the water elm, and its 
seeds usually were found in. company with the seeds of that plant 
in the stomachs of wood ducks. One stomach and distended crop ° 
were found which held 157 of these large seeds, with remains of 
several more. A sprig of swamp privet was sent to the Biological 
Survey by C. G. Wright; of Dallas, Tex., with the statement that it 
was grown from seed taken from a wood duck’s gizzard, which was 
absolutely full of them. 
MISCELLANEOUS VEGETABLE FOOD, 9.4 PER CENT. 
A great number of smaller items, each of which amounted to less 
than 1 per cent, made up the remainder of the wood duck’s vegetable 
food. In some localities the ducks had fed upon the tubers and 
seeds of arrowheads (Sagittaria latifolia and other species) ; and three 
from Caruthersville, Mo., had stuffed themselves with the stems, 
leaves, and rootstocks of a crowfoot (Ranunculus sp.). Three taken 
in Okefenokee Swamp, Georgia, in December, 1916, had been feeding 
upon the crimson rootstocks of red-root or paint-root (Gyrotheca 
20 McAtee, W. L., Eleven Important Wild-duck Foods, Bull. No. 205, U.S. Dept. of Agr., pp. 12-13, 1915. 
