22 BULLETIN 862, U. S. DEPARTMENT OF AGRICULTURE. 
shells or bits of shell probably are often taken by ducks in lieu of 
gravel to help grind the food, but there is no doubt that the mollusks 
themselves, and especially snails, are relished by the birds and form 
an important element in their food. Three genera of snails were 
identified: Physa, Neritina, and Planorbis. Unidentified snails were 
taken from 44 stomachs, and bivalves from only 3. Broken mollusk 
shells, unclassified, were found in 90 gizzards. 
CRUSTACEANS (CRUSTACEA), 0.92 PER CENT. © 
Small crustaceans, which are abundant in numbers and variety 
in nearly all streams and bodies of water, whether salt or fresh, are 
sought by nearly all ducks. They furnished 0.92 per cent of the total 
food of the green-winged teal, or approximately one-tenth of the 
animal food. Chief among these were the ostracods, small bivalved 
crustaceans which might easily be mistaken for minute mollusks. 
Small shrimplike crustaceans known as amphipods were taken in 
some numbers, and in one stomach the claws of an unidentified crab 
were found. 
MISCELLANEOUS ANIMAL FOOD, 0.25 PER CENT. 
A few spiders and mites (class Arachnida), centipeds (Myriapoda), 
fish scales, minute aquatic animalculae, and other insignificant items 
form the remainder of the green-winged teal’s animal food. 
BLUE-WINGED TEAL. 
(Querquedula discors.) 
PLATE EV: 
The blue-winged teal, blue-wing, or summer teal is slightly more 
restricted in its distribution than the green-wing. Although it has 
been recorded as breeding in Rhode Island, Maine, New Brunswick, 
Nova Scotia, Newfoundland, Quebec, Ontario, and New York, and 
as far south as northern Ohio, southern Indiana, southern Colorado, 
New Mexico, Texas, Utah, northern Nevada, and central Oregon, 
it is not common east of the Allegheny Mountains nor on the Pacific 
slope. Its principal summer home is in. the interior of North America 
between the Rocky Mountains and the Great Lakes, from northern 
Illinois and Nebraska north to Saskatchewan. Its principal range 
extends north to British Columbia, and it occurs also rarely north to 
Alaska, Alberta, and about Great Slave Lake. In winter, blue-winged 
teals are found throughout northern South America south to Brazil, 
Ecuador, Peru, and Chile; they occur abundantly in Central America, 
Mexico, and the West Indies; and in the United States they are found 
near the Gulf, and as far north as North Carolina, and (sparingly) 
southern Indiana and southern Illinois. Unlike the green-winged teal, 
this is one of the least hardy of our ducks, migrating late in spring 
