402 AVES. 
ORDER VI. 
PALMIPEDES. 
These birds are characterized by their feet, formed for 
natation, that is to say, placed far back on the body, attached 
to short and compressed tarsi, and with palmated toes. Their 
dense and polished plumage saturated with oil, and the thickly 
set down which is next to their skin, protect them from the 
water in which they live. ‘They are the only birds whose 
beak surpasses—which it sometimes does to a considerable ex- 
tent—the length of their feet, and this is so, to enable them to 
search for their food in the depths below, while they swim on 
the surface. Their sternum is very long, affording a com- 
plete guard to the greater part of their viscera, having, on 
each side, but one emargination or oval foramen, filled up 
with membrane. Their gizzard is usually muscular, the ceca 
long, and the inferior larynx simple; in one family, however, 
the latter is so inflated as to form cartilaginous capsules. 
This order admits of a tolerably precise division into four 
families. 
FAMILY I. 
BRACHYPTERZ. 
A part of this family has some external affinities with that of 
the Gallinule. ‘Their legs, placed further back than in any 
other birds, renders walking painful to them, and obliges them, 
when on land, to stand vertically. In addition to this, as 
most of them have but feeble powers of flight, and as some of 
them are wholly deprived of that faculty, we may consider 
them as exclusively attached to the surface of the water: 
their plumage is extremely dense, and its surface frequently 
polished, presenting a silvery lustre. ‘They swim under wa- 
ter, using their wings with almost as much effect as though 
they were fins. Their gizzard is muscular, and their ceca 
