ANATINiE. TADORNA. 
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moderate ; tibia bare for a very short space ; tarsus 
short, compressed, reticulated, with very small anterior 
scutella ; hind toe very small, elevated, with a lobiform 
membrane ; inner toe much shorter than the outer, which 
is nearly equal to the third, all scutellate above ; inter- 
digital membranes full ; claws small, compressed, little 
arched, rather acute, that of the middle toe expanded 
internally. Plumage dense, firm, elastic, soft, blended ; 
feathers of the head and upper neck small, of the other 
parts large ; scapulars large ; wings moderate, rather 
narrow, pointed ; first and second quills longest ; inner 
secondaries oblong ; tail moderate, nearly even, of more 
than twelve feathers. 
The Anatinse feed on seeds, roots, mollusca, insects, 
worms, and occasionally other substances. The males 
are always larger, and usually differently coloured. Some 
of the secondary quills are highly coloured, with silky or 
metallic lustre, forming what is technically named the 
speculum. Toward the end of summer, the males become 
similar to the females in plumage, but in autumn resume 
their proper colours. The nest is placed on the ground, 
or in holes ; the eggs numerous, white, greenish, or of some 
uniform light tint. The young, covered with stiffish 
down, presently betake themselves to the water. Some 
of these birds occur in all climates, frequenting marshy 
places, lakes, and rivers. They procure a great part of 
their food by thrusting the head under the water, but 
they seldom dive. 
GENUS CXXIY. TADORNA. SHIELDUCK. 
The species of this genus bear a considerable resemblance 
in form to those of the genus Anser. The body is large, 
full, rather elongated, about the same height and breadth ; 
the neck rather long and slender ; the head moderate, ob- 
long, compressed, rounded above. Bill as long as the head, 
higher than broad at the base, gradually depressed, consi- 
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