In these islands a great loggerheaded duck or goose (Anas
brachyptera), which sometimes weighs twenty-two pounds,
is very abundant. These birds were in former days called,
from their extraordinary manner of paddling and splashing
upon the water, race-horses; but now they are named, much
more appropriately, steamers. Their wings are too small and
weak to allow of flight, but by their aid, partly swimming and
partly flapping the surface of the water, they move very
quickly. The manner is something like that by which the
common house-duck escapes when pursued by a dog; but I
am nearly sure that the steamer moves its wings alternately,
instead of both together, as in other birds. These clumsy,
loggerheaded ducks make such a noise and splashing, that the
effect is exceedingly curious.

Thus we find in South America three birds which use their
wings for other purposes besides flight; the penguins as fins,
the steamer as paddles, and the ostrich as sails: and the
Apteryz of New Zealand, as well as its gigantic extinct
prototype the Deinornis, possess only rudimentary
representatives of wings. The steamer is able to dive only
to a very short distance. It feeds entirely on shell-fish
from the kelp and tidal rocks: hence the beak and head, for
the purpose of breaking them, are surprisingly heavy and
strong: the head is so strong that I have scarcely been able
to fracture it with my geological hammer; and all our sportsmen
soon discovered how tenacious these birds were of life. When in
the evening pluming themselves in a flock, they make the same
odd mixture of sounds which bull-frogs do within the tropics.