bulky, is about one-eighteenth
of the length of the head of a moderately large Balaenoptera rostrata,
in which species the baleen is only nine inches long; so that if we were
to make the head of the shoveller as long as that of the Balaenoptera,
the lamellae would be six inches in length, that is, two-thirds of the
length of the baleen in this species of whale. The lower mandible of
the shoveller-duck is furnished with lamellae of equal length with these
above, but finer; and in being thus furnished it differs conspicuously
from the lower jaw of a whale, which is destitute of baleen. On the
other hand, the extremities of these lower lamellae are frayed into
fine bristly points, so that they thus curiously resemble the plates
of baleen. In the genus Prion, a member of the distinct family of the
Petrels, the upper mandible alone is furnished with lamellae, which are
well developed and project beneath the margin; so that the beak of this
bird resembles in this respect the mouth of a whale.

From the highly developed structure of the shoveller's beak we may
proceed (as I have learned from information and specimens sent to me by
Mr. Salvin), without any great break, as far as fitness for sifting
is concerned, through the beak of the Merganetta armata, and in some
respects through that of the Aix sponsa, to the beak of the common
duck. In this latter species the lamellae are much coarser than in the
shoveller, and are firmly attached to the sides of the mandible; they
are only about fifty in number on each side, and do not project at
all beneath the margin. They are square-topped, and are edged with
translucent, hardish tissue, as if for crushing food. The edges of the
lower mandible are crossed by numerous fine ridges, which project very
little. Although the beak is thus very inferior as a sifter to that of
a shoveller, yet this bird, as every one knows, constantly uses it for
this purpose. There are other species, as I hear from Mr. Salvin, in
which the lamellae are considerably less developed than in the common
duck; but I do not know whether they use their beaks for sifting the
water.

Turning to another group of the same family. In the Egyptian goose
(Chenalopex) the beak closely resembles that of the common duck; but the
lamellae are not so numerous, nor so distinct from each other, nor do
they project so much inward; yet this goose, as I am informed by Mr. E.
Bartlett, "uses its bill like a duck by throwing the water