William Beebe.

The bird, its form and function online

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appearance jet-black or parti-coloured shavings.

The nuptial plumes of the Night Heron hang far down
upon its shoulders, and the soft barbs are curved inward,



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26o The Bird

forming a slender tube. The glory of the Great Crowned
Pigeon is a maze of lavender lacework, — one of the most
beautiful of all crests; while the most graceful, perhaps,
is the mist of filmy whiteness which, at the slightest breath
of air, floats about the neck of the Snowy Egret, like
the mantilla of a senorita. Cockatoos are decorated
with a profusion of beautiful crests, each characteristic.
These are under the complete control of the birds, and
take an important part in expressing changing moods
and emotions. The crests may lie so flat as to be ordi-
narily invisible, when, in a flash, the whole head is sur-
mounted by an auriole of colour or whiteness. An ex-
cited Leadbeater Cockatoo is a wonderful sight. Before
the crest is raised, all that is visible is a single, rather
elongated white feather, but a wealth of colour is hid-
den, which flares out, showing a band of scarlet close to
the head, next a streak of bright yellow, then a second
band of red, and finally the white tips of the crest feathers.
The nod or jerk of the head in spreading wide the crest
reminds one of the sudden flick with which a fan is thrown
open.

Concealed crests bring to mind the Kingbird and the
Ruby-crowned Kinglet, both of which derive their names
from their crowns of ruby. It is said that the former
bird is aided in ite search for food by the bright spot
of colour which, flower-like when exposed, attracts in-
sects. This, however, should be confirmed before being
accepted as a fact; although in a tropical flycatcher,
which has a beautiful red and purple transverse crest, the
evidence of this novel use seems fairly well corroborated.



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Fio. 202.— Crest of Banded Curasaow (female).



Fio. m.-CTest of \'ictoria Crowned Pigeoi^ig^.i^^^ byQoOgle



Fig. 204. — Harpy Eagle. (Courtesy of Dr. Frank Baker.)

262



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Heads and Necks 263

The Laughing Thrush of the Himalaya Mountains
has every feather upon its head lengthened and perma-
nently erect, forming a soft, spreading halo.



Fig. 205. — Hooded Merganser. (From a photograph provided by the American
Museum of Natural History.)

In almost every Family of birds we find certain spe-
cies with long, well-developed crests. Among the ducks,
the Hooded Merganser has a compressed, semicircular
halo of delicate feathers, while the Mandarin Duck has
a broad, many-coloured, erectile crown, which is con-



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264 The Bird

spicuous even in contrast with the gorgeous ornamenta-
tion of the body of this feathered harlequin. Of birds
of prey, the Harpy Eagle has perhaps the most imposing
crown of feathers.

Sometimes the crest is sharply set off from the rest
of the bird's plumage, as in the scarlet-plumed wood-
peckers, whose crests give them the appearance of having
long hair, which is gracefully brushed straight backward
and upward.

We must not discuss the subject of crests without men-
tion of two birds of extraordinary appearance, the Crowned
Crane and the Umbrella-bird. The former illustrates
admirably what strange and unfeather-like forms, feathers
may assume in the course of evolution. The illustration
shows better than words can describe the dense, velvety
cap of plush-like feathers, and the glorious crown of a
myriad radiating points — a decoration unrivalled, even
among birds, in exquisite colour and delicacy. In addi-
tion to this, the cheeks are entirely bare of feathers, and
the lower half suffused with blood, which shows through
the skin, — an ever-changing blush of deep pink.

The decorations of the Umbrella-bird are as beautiful
as they are bizarre; while if shorn of its crest and streamers,
this bird would resemble a small crow in appearance.
The crest really bears a resemblance to the article which
has given the bird its name — a high, arching mass of
feathers, overshadowing the entire head and beak, con-
tinually spreading and partly closing again, as the bird's
emotions change. From the neck of the bird dangles a
streamer of black feathers, as long as the bird's entire



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Heads and Necks 265



>



Fig. 206 —Crowned Crane.



Fig 207. — Demoiselle Crane.



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266 The Bird

body and which, when it flies, blows back between its
feet. The filament of feathers looks for all the world
as if a strip of the bird's plumage had caught on a thorn
and torn loose. The core of the streamer is a very slender




Fig. 208.— Umbrella-bird.

ribbon of skin which hangs from the neck. Would that
we could state the causes and the manner of the devel-
opment of these curious structures which our fancy likens
to an umbrella and a feathery handle!

One or two small tufts of feathers may spring from



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Heads and Necks 267

some part of the head of a bird, such as the feather "homs "
of owls, motmots, and larks. In Screech Owls these
prominent ''ears" certainly play a useful part in breaking
up the outline of the bird, rendering it ver}- difficult of
detection when it is perched upon some jagged limb or
stub. Or again, tufts or pencils of feathers may arise
from near the ear, or over the eye; as shown by the Dem-
oiselle Crane (Fig. 207), some of the Puffins, and the Man-
churian Pheasants (Fig. 209). The Great Bustard has long
tufts of chin-feathers which, like wide-spreading whiskers,
spread to each side, and the Bearded Vulture has a simi-
lar goatee of stiff, black bristles.

Of the wonderful crests, frills, ruffs, breastplates, and
cloaks of hummingbirds there is no room to speak, and
indeed no words or pictures can aught but parody them.
The eye alone can record their marvels, in the collection
of a museum, or, better still, in the living birds, as the
little creatures hover over their favourite flowers, or
vibrate before us, fanning the air in our verj^ faces with
their invisible wings.

Brief mention should be made of two Birds of Para-
dise, those beautiful creatures inhabiting a region where
the eye of man seldom sees them.

The Six-shafted Bird of Paradise is found only in
New Guinea. ''The plumage appears at first sight black,
but it glows in certain lights with bronze and deep pur-
ple. The throat and breast are scaled with broad, flat
feathers of an intense golden hue, changing to green and
blue tints and certain lights. On the back of the head
is a broad recurved band of feathers, whose brilliancy



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Fig. 209.— Head of Eared Pheasant.



Fig. 210.— Head of Great Horned Owl. Digitized by CiOOQle

268 ^



Heads and Necks 269

is indescribable, resembling the sheen of emeralds and to-
paz, rather than any organic substance. Over the fore,
head is a patch of pure white feathers, which shine like
satin; and from the sides of the head spring the six won-
derful feathers.''



Fig. 211. — Six-shafted Bird of Paradise (a mounted bird). (From a photo-
graph provided by the American Museum of Natural History.)



Head decorations reach the acme of strangeness in
the King of Saxony's Bird of Paradise. The bird itself
is sombre-hued and small, about the size of our robin,
with nothing unusual about its appearance, except for
the two streamers springing from opposite sides of the



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270 The Bird

head. They are twice (or more) the length of the body,
and, far from being feather-like, they are best described
as a series of thirty or forty tiny flags of blue enamel,
each separate, each hanging pendent from the main
shaft (Fig. 212). It would seem as if Nature heraeif
could go no farther in unusual decoration than this.



Fig. 212.— King of Saxony Bird of Paradise. (From a photograph provided
by the American Museum of Natural History.)

In the Double-crested Pigeon of Australia the core
or fleshy covering of the beak is completely feathered;
while some of the birds known as plantain-eaters are
feathered to the very tip of the short beak with plumes
of delicate green, tipped with white. The extreme of
feathering is shown by the Cock-of-the-Rock, in which



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Heads and Necks 271

the whole beak, in fact every part of the head except the
eyes, is buried in a maze of soft, orange plumes.

As the antithesis to this condition, we find many
birds which have the head partly or entirely bare of
feathers, such as the vultures and some of the waders.

In the former group this lack of feathers is doubtless



Fig. 213.— Head of male Condor

of value in enabling the birds to avoid soiling their plu-
mage, when engaged in their scavenger work. The great
Condor of South America has, just below this naked area,
a necklace of the whitest of fluffy down, and in addition
the male has a large wattle of skin upon the front of the
head. The Caracara of Mexico is partly vulturine in its
habits, and the feathers have disappeared from part of
its face. Wherever the skin of the head and neck is even



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2/2 The Bird



FiQ. 214. — Caracara. partly vulturine in habits.



FiQ. 215.— Young King Vulture.



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Heads and Necks 273

partly bare, ornamentation often takes the form of many-
shaped and often highly coloured wattles, such as we see
highly developed in a King Vulture.

The most common example of this is seen in a domestic
rooster or a turkey, but in many other birds these wat-
tles of skin are very brilliant in hue. Indeed the casso-
waries are resplendent in their gorgeous hues of blue, yel-
low, red, and many other intermediate shades. Turkeys
too, at the breeding season, develop bright colours.
The Yucatan Wild Turkey, which has thus far resisted
all attempts at domestication, has the bright blue naked
skin of the head, dotted with tubercles of the most bril-
liant orange, while a long tube-like wattle, also tipped
with orange, dangles down over the beak. The wattles,
or caruncles, of the Bell Bird are interesting as being con-
nected with the windpipe in such a way that they become
inflated with air when the bird utters its wonderful note.

In the White Ibis the face only is bare, in the spoon-
bill the head and face, and the whole head and neck in
the Marabou Stork; the effect of this condition in the
latter bird being heightened by the enormous pouch
which hangs suspended from the neck. The same is true
of the Adjutant.

A close inspection of the neck of one of these storks
will show that, while ordinary feathers are absent, there
is a scanty covering, here and there, of what looks like soft,
curling ringlets of chestnut hair. The resemblance is
absolutely perfect, and no naturalist in the world, if shown
one of these locks, would say that it came from a bird
and not from one of the hair-covered mammals !



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Fio« 216. — Head of domestic cock. Extreme development of comb.



Fig. 217. — Head of domestic cock. Extreme development of crest.

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Heads and Necks 275

We must pass by all the strange ornaments of horn
upon the heads of birds, such as the scarlet plate of the
gallinules, the immense recurved casques of the hornbills,
the use of which is as yet unknown, unless it be purely
ornamental. But the impressive helmets of the cassowaries,



Fig. 218.— Head of Wild Turkey.

Fig. 228, demand especial notice in this volume, as being very
useful adaptations to life in a dense forest. These great
running birds are the only members of their Sub-class
which inhabit thickly forested regions, and in speeding
with great leaps and bounds through the undergrowth, the
tall, smooth helmet of horn protects the head of the bird



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276 The Bird



Fio. 219.— Head of Adjutant.



Fig. 220.— Ringlet of hair from the neck of an Adjutant.



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Heads and Necks 277

and shunts oflf the hanging lianas and vines which would
otherwise impede its progress.

In our hasty paragraphs we have seen to what a re-
markable extent the ornamentation of the heads of birds
is carried, and as many extraordinary examples could
be given of decoration of the neck. The Loon has a
speckled black and white throat with a long colour band-
age of black feathers wound about its neck; the cervical
ruffs of our Ruffed Grouse are like wings in miniature;
in the Golden and Amherst Pheasants this form of orna-
ment is extended into a circular ruff of black and gold
and black and white respectively; while in the Superb
Bird of Paradise a shoulder-cape flares back, large enough
to cover almost the entire body of the bird, giving it the
appearance of being clothed in two distinct sets of plu-
mage! The nuptial attire of the Ruff, a species of sand-
piper, is as greatly developed, except that it forms a
double cloak over the breast.

This cloak or shield of feathers in the Ruff plays a
vital part in the life of the bird. We must first notice
the remarkable variation in the pattern of this cloak of
battle, — for such it really is. If we could see fifty Ruffs
standing side by side, some would be seen to have ruffs
of pure white, others of gray, black, orange, buff, or chest-
nut, while the wavmg ear-plumes are also independent
in colour, varying from white to purple, green, or blue.
Then there is a type of Ruff with barred cloaks, another
with spotted patterns, and so on in almost endless
variation. This condition of affairs is wholly unlike
the uniform pattern of colouring of other wild birds.



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278 The Bird



Fio 221.— Lady Amherst Pheasant.



Fig. 222.— Casque of Hornbill.



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Heads and Necks 279

We can only compare these little Joseph-coated birds
with the unnatural sports among domestic poultry and
pigeons.

But whatever their colour, these Fighting Snipe find
their ruflfs of service in their encounters at the breeding
season. Four male birds which I observed in captivity



Fia. 223. — Ruff with battle-cloak partly moulted.

were adorned respectively, — plain gray, dotted gray,
chestnut barred with black, and a rich golden rufous.
Though no females were present, yet their fighting instinct
often cropped out and a pair of them would dart and side-
step about each other, bills held low and far advanced,
ruflf spread out from the breast and trailing low, hiding
almost the whole body. Now and then one of the fencers
would make a vicious dash, sending his bill through the



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28o The Bird

feather shield of his opponent. But the force of the
blow would spend itself on the inch of space between the
shield and the feathers of the bird's breast. When, in
his native haunts, the Ruff has conquered his rival, his
triumphant dances before the female are most elaborate.
While these facts are not exactly pertinent to the physical



Fig. 224.— Breast ornament of a Wild TurkeycxMjk.

life of the bird, yet I mention them to show to what prac-
tical, as well as aesthetic, uses the development of some
portion of the bird's plumage may be devoted.

What a contrast to the cloak of the Ruff is the pectoral
decoration of the Wild Turkey cock: a great tuft of
coarse, black hair-Hke feathers, like the tail of a horse



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Heads and Necks 281

in miniature, growing almost a foot in length from the
centre of the breast !

The length of the neck of birds is often correlated
with that of the legs, — a long-legged bird of necessity re-
quiring a long neck to permit its bill to reach the ground.
Geese and swans are an exception, and in their case we



Ftg. 225.— Flamingoes Correlation of long neck with long legs.

find that the long, mobile neck is of great use in making
up for the awkwardness of their waddle when on land,
and in allowing them to reach beneath them while floating
in shallow water, thus feeding along the bottom.

Herons are uniformly so light of body that they would
have difficulty in steadying themselves in the air, were
it not that, when in flight, their necks become compressed
to an incredible thinness, thus acting as does the cut-



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282 The Bird

water of a ship's prow. The perpetual crook in the necks
of these birds is significant of their method of fishing — a
patient watch until the prey comes within striking distance-
In the snake-bird this crook, or Z-shape, has, by the



Fig. 226. — Swan. Correlation of long neck and short legs due to feeding habits.

(Sanborn, photographer.)

adaptation of three of the neck-bones, become a veritable
trigger, by the springing of which the bird literally spears
the fish.

If the mention in this chapter of a few examples of
crests and other decorations has seemed in the least to



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Heads and Necks 283

verge upon the monotony of a mere catalogue, my plea
is that they have been cited with the intention of empha-
sizing the fact of the remarkable degree which decoration,
pure and simple, plays in courtship. Viewed from such
a standpoint, these facts and comparisons become im-
portant data in the observation of the courtship of birds,



Fig. 227. — Snake-bird, showing crook in neck.

which in its turn is one of the most important and interest-
ing corollaries of the psychology of these beings. Whether
female birds have highly developed aesthetic feelings, or
whether the songs and dances and colour masses act more
along the line of the passes of a hypnotist, is yet to be
ascertained.

It is also hoped that a realization of the more immedi-



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284 The Bird

ately practical uses of such structures as the cassowary's
horny helmet, the feather shield of the Ruff, perhaps the
crest of the kingbird, and many others as yet unknown,
will impel amateur observers to further efforte in the
investigation of the life-habits of birds.



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CHAPTER XII
THE BODY OF A BIRD

N experimenting with balloons and flying-ma-
chines, weight is a question of prime import-
ance, and among birds there seem to be certain
limits to the bulk of the body, beyond which flight is
impossible. The tiny hummingbirds, with bodies weigh-
ing less than some insects, have remarkable powers of
flight, and throughout all the groups of larger birds we
find certain species with exceptional flight ability, until
in the birds of widest extent of wing, such as the condor
and the albatross, flight seems to reach the acme of perfec-
tion. But the flying birds of actual heaviest bulk are
perhaps the Wild Turkey, the Great Bustard, and the
Trumpeter Swan, the two latter reaching weights of thirty-
two and twenty-five pounds respectively. Even the
gigantic Pterodactyls , those flying reptiles of olden time,
some of which had heads a yard long, and an expanse of
eighteen feet or more of bat-like wings, are estimated
to have weighed but twenty pounds or thereabouts.

But when the necessity for flight ceases, a bird may
begin to assume larger proportions and greater weight
without detriment; just as a mammal which adopts a fife

in the dense medium of water may attain a much more

285



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286 The Bird

gigantic size than one which has to support its body in
the thinner atmosphere: a whale is to a horse as an
ostrich is to a dove.

The ostrich is the largest of all living birds, a full-
grown male being able to reach to a height of nine feet
and weighing as much as three hundred pounds; but
even these figures were exceeded by its extinct relative
of Madagascar, the moa, whose height is variously esti-
mated at from ten to eleven feet, and whose massive leg-
bones show that its weight must have been much greater
than that of the ostrich.

There is a great difference in the relative condition
of the body in various birds. Herons, even when fish
are abundant, with opportunities of feeding from morn-
ing to night, are thin to emaciation. Truly they belong
to the **lean kine." A fat heron would be an anomaly.
On the other hand, the flesh of many sea-birds seems as
constantly encased in thick, oily layers of fat. Petrels
are used by the inhabitants of some islands as candles,
simply by threading the body of the dead bird with a
wick, the excess of fat burning steadily until the whole is
consumed. Penguins are well protected against the icy
waters of their Antarctic home by a layer of fat under
the skin, so thick in proportion to their size as to remind
one of the blubber of whales.

If we were writing of the bodies of the fur-bearers
instead of birds, we would have much to say concerning
the various kinds of scent-glands and secreted odours;
but in birds the only gland is that above the tail, which
furnishes the oil with which the bird preens its plumage,



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The Body of a Bird 287

thus both cleansing it and rendering it water-proof. That
birds, and especially those which, like quail, are found
in flocks, possess odours is borne witness to by the ability
of dogs to point successfully the hidden game; but that
this is of much use in enabling the birds to find one another
is doubtful, both from the fact of the slight development
of the sense of smell, and because of the loud call-notes
which are so characteristic of these birds. One exception,
however, may be noted, that of the apteryx, which is
said to have a strong and persistent odour, with corre-
spondingly well-developed nostrils.

Again, among fur-covered animals we find usually
a poor development of the sense of sight and but few
of them exhibit bright colours, while, as we have seen,
birds excel in the power of seeing, and, correlated with
this, possess an unparalleled array of colours upon the
body.

There are many ways in which the body or its feathers
are adapted to aid the bird in some special way. For
example, the PuflF-back Shrike of Africa has a habit of
suddenly puffing out and erecting a patch of long, loose,
white feathers on its back, giving the appearance of a
large powder-puflf, an act so startling and unexpected
being well calculated to make any attacking hawk or
other bird hesitate.

The general texture of the body feathers is usually
an accurate index to the bird's power of flight. Although
the feathers of the breast and back are never as compact
or as stiff as those of the wings and tail, yet in birds of
good flight their barbs are quite firmly connected. In a



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288 The Bird

small African bird, called from its habits the Rock-jumper,
the wings are so small that the power of flight is almost
nil, and we find an interesting corollary in the plumage,



Fig. 228. — Cassowary, showing the loose plumage of a flightless bird. (Sanborn,
photographer. Courtesy of N. Y. Zoological Society.)

which is so loose and fluffy that it blows about in the
least wind. In the ostrich and rhea this down-like char-
acter is still more noticeable and extends even to the
feathers of the wings and tail. The extreme is to be found



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The Body of a Bird 289

in the apteryx and emeu (Fig. 23). Compare a feather
of the latter with one of a condor and the difference is
remarkable. So unfeatherlike is the emeu's plume and
so loose are its barbs that it brings to mind the much-
divided leaflets of an Acacia.

The plumage of the snake-bird is inexplicable. This
bird is so emphatically aquatic that we would expect
a dense, compact covering of the body; but in reality
it more nearly resembles hair or fur, soaking through so
quickly and thoroughly that, after immersion for some
time, the bird becomes waterlogged and has to hang
itself out to dry by seeking some sunlit perch, opening
wide its wings and waving them to and fro.

The feathers of the penguin are small, flat, and rigid,
approaching in these respects the scales of fishes — an
interesting reacquinng of characters consequent upon
an all but wholly aquatic life. It is interesting to com-
pare the colouring of such a bird as the Scaled Partridge
with a fish like the Carp, the dark margins of the feathers
and scales bringing about a remarkable resemblance.

Taking up the subject of colour in general, we realize,
after even a superficial glance at a collection of birds,
that in gorgeousness of hue and diversity of shade and pat-
tern, they are to be compared only with insects. In a
former chapter we have briefly considered the chemical
and optical causes of colour in feathers; but the causes


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Online LibraryWilliam BeebeThe bird, its form and function → online text (page 12 of 22)