The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1899-08-29

right, the experiment did not succeed.
and the pterodactyls have left no de-
scendant. But another group of reptiles
developed feathers and became the an
cestors of class that was to dispute
with the mammalia the highest rank in
the organic world. Feathers help flight
not only indirectly by keeping up Il e
body's temperature, but directly Ivy
their structure. Birds of the duck fam
lily, that moult all the chief wing feaLh-
ers at once, are unable to fly until
new set has grown. But birds have
found a further use for feathers. Placed
above immediate want by their higher
organization, they have been enabled TO
give considerable share of their at
tention to matters beyond the bare
necessities of existence. The greater
development of the brain has made
possible the cultivation of an aesthetic
sense. The feathers, therefore-almoat
the only parts exposed to view--hnve
been used for decorative purposes in
this the birds have set an example that
they have since had reason to regret.
To examine more closely the various
uses of feathers it will be necessary TO
consider the structure of feathers, their
various forms and colors and their dis
tribution over the surface of the boy.
The appearance of an ordinary wing
or tail feather Is familiar to ALL 1t
consists of hollow, transparent quill,
continued as a solid and Opaque shaft
fringed with barbs. These barbs in
their turn bear barbules and these
again give off barbicles. 1t is the barb
ules and barbicles that give the feather
its value in flying and steering. If the
barbs were allowed to stream out indie
pendently the feather would offer little
resistance to the air and would there
fore be useless as a lever to propel or
guide the bird in flight. AS everyone
has observed, however, the barbs of
quill feathers cling together. This Is
effected by means Of the barbules and
barbicles. Each barb carries two kinds
of barbules, each kind confined to one
side of the barb. Those on the side to-
ward the base of the feather have
doubled-in margins, to which cling the
hooked barbicles of the adjoining barb.
AS the barbules cross each other at a
considerable angle, each of the hook
bearing set is attached to about five of
the doubledin set, and each Of these is
held by the same number of hooks be-
longing to different barbules of the next
barb. The wing and tail feathers of
the type described are classed with the
ordinary feathers that form the general
covering Of the body as contour feath-
ers."
OF the remaining varieties the chief
are those known as downs and flo
plumes or threadfeathers. Many feath-
ers appear double owing to the pres
ence of a supplementary shaft springing
from the same quill and bearing barbs
and barbules, but no barbicles. This
aftershaft," as it is called, may be
equal in size to the main shaft, as in
the cassowary and emu, or 1t may be
small or absent, as in the ostrich. 1t Is
best developed in downs and in small
contour feathers. The downs ows their
loose appearance to the absence of the
booklets that bind together some,
though not all, of the contour feathers.
In some downs all the barbs start from
one point. Ffloplumes are the result
of the suppression of the barbs.
Flying birds have always, in their
adult state, feathers with interlocked
barbs. Downs and filoplumes are found
only under the contour feathers, as as
ISOLATED with them. In running birds
a structure that would offer much re-
sistance to the air would be hind
rance rather than an advantage. This
is probably the explanation of the loose
flowing contour feathers of the ostrich
and in the bare spines of the casso-
wary's wings. So in the penguin, which
uses it's wings under water, the feath-
ers have been reduced almost to scales
and lie close to the body.
In the same birds we find an unusual
distribution of feathers. due apparent
feathers, on other parts of the body
as we'll as the wings and tail, appear
to be of some use in flight. 1t would,
therefore, be more advantageous for a
flying bird to have its feathers in we'll
defined patches, capable of independent
movement, than to have them spread
equally over the whole body We find,
accordingly, that very few birds have
continuous covering of feathers. In
the penguin, the ostrich and the apt
erik, however, the feathers are equally
distributed and thus offer less resist
ance to the water or air.
The colors of feathers are produced
in several ways. They may be due
to the presence of pigment or to struct-
ure or to both. Red, black and brown
are always pigmental colors. They are
unaffected by the angle by which the
light falls or the direction in which
they are looked at. Whether by re-
Elected or by transmitted light, they