Family XVI. PICINAE. WOODPECKERS. GENUS I. PICUS, Linn. WOODPECKER. |
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Family |
THE IVORY-BILLED WOODPECKER. [Ivory-billed Woodpecker. PRESUMED EXTINCT.] |
Genus | PICUS PRINCIPALIS, Linn. [Campephilus principalis.] |
I have always imagined, that in the plumage of the beautiful Ivory-billed
Woodpecker, there is something very closely allied to the style of colouring of
the great VANDYKE. The broad extent of its dark glossy body and tail, the large
and well-defined white markings of its wings, neck, and bill, relieved by the
rich carmine of the pendent crest of the male, and the brilliant yellow of its
eye, have never failed to remind me of some of the boldest and noblest
productions of that inimitable artist's pencil. So strongly indeed have these
thoughts become ingrated in my mind, as I gradually obtained a more intimate
acquaintance with the Ivory-billed Woodpecker, that whenever I have observed one
of these birds flying from one tree to another, I have mentally exclaimed,
"There goes a Vandyke!" This notion may seem strange, perhaps ludicrous, to
you, good reader, but I relate it as a fact, and whether or not it may be found
in accordance with your own ideas, after you have inspected the plate in which
is represented this splendid species of the Woodpecker tribe, is perhaps of
little consequence.
The Ivory-billed Woodpecker confines its rambles to a comparatively very
small portion of the United States, it never having been observed in the Middle
States within the memory of any person now living there. In fact, in no portion
of these districts does the nature of the woods appear suitable to its
remarkable habits.
Descending the Ohio, we meet with this splendid bird for the first time
near the confluence of that beautiful river and the Mississippi; after which,
following the windings of the latter, either downwards toward the sea, or
upwards in the direction of the Missouri, we frequently observe it. On the
Atlantic coast, North Carolina may be taken as the limit of its distribution,
although now and then an individual of the species may be accidentally seen in
Maryland. To the westward of the Mississippi, it is found in all the dense
forests bordering the streams which empty their waters into that majestic river,
from the very declivities of the Rocky Mountains. The lower parts of the
Carolinas, Georgia, Alabama, Louisiana, and Mississippi, are, however, the most
favourite resorts of this bird, and in those States it constantly resides,
breeds, and passes a life of peaceful enjoyment, finding a profusion of food in
all the deep, dark, and gloomy swamps dispersed throughout them.
I wish, kind reader, it were in my power to present to your mind's eye the
favourite resort of the Ivory-billed Woodpecker. Would that I could describe
the extent of those deep morasses, overshadowed by millions of gigantic dark
cypresses, spreading their sturdy moss-covered branches, as if to admonish
intruding man to pause and reflect on the many difficulties which he must
encounter, should he persist in venturing farther into their almost inaccessible
recesses, extending for miles before him, where he should be interrupted by huge
projecting branches, here and there the massy trunk of a fallen and decaying
tree, and thousands of creeping and twining plants of numberless species! Would
that I could represent to you the dangerous nature of the ground, its oozing,
spongy, and miry disposition, although covered with a beautiful but treacherous
carpeting, composed of the richest mosses, flags, and water-lilies, no sooner
receiving the pressure of the foot than it yields and endangers the very life of
the adventurer, whilst here and there, as he approaches an opening, that proves
merely a lake of black muddy water, his ear is assailed by the dismal croaking
of innumerable frogs, the hissing of serpents, or the bellowing of alligators!
Would that I could give you an idea of the sultry pestiferous atmosphere that
nearly suffocates the intruder during the meridian heat of our dogdays, in those
gloomy and horrible swamps! But the attempt to picture these scenes would be
vain. Nothing short of ocular demonstration can impress any adequate idea of
them.
How often, kind reader, have I thought of the difference of the tasks
imposed on different minds, when, travelling in countries far distant from those
where birds of this species and others as difficult to be procured are now and
then offered for sale in the form of dried skins, I have heard the amateur or
closet-naturalist express his astonishment that half-a-crown was asked by the
person who had perhaps followed the bird when alive over miles of such swamps,
and after procuring it, had prepared its skin in the best manner, and carried it
to a market thousands of miles distant from the spot where he had obtained it.
I must say, that it has at least grieved me as much as when I have heard some
idle fop complain of the poverty of the Gallery of the Louvre, where he had paid
nothing, or when I have listened to the same infatuated idler lamenting the loss
of his shilling, as he sauntered through the Exhibition Rooms of the Royal
Academy of London, or any equally valuable repository of art. But, let us
return to the biography of the famed Ivory-billed Woodpecker.
The flight of this bird is graceful in the extreme, although seldom
prolonged to more than a few hundred yards at a time, unless when it has to
cross a large river, which it does in deep undulations, opening its wings at
first to their full extent, and nearly closing them to renew the propelling
impulse. The transit from one tree to another, even should the distance be as
much as a hundred yards, is performed by a single sweep, and the bird appears as
if merely swinging itself from the top of the one tree to that of the other,
forming an elegantly curved line. At this moment all the beauty of the plumage
is exhibited, and strikes the beholder with pleasure. It never utters any sound
whilst on wing, unless during the love-season; but at all other times, no sooner
has this bird alighted than its remarkable voice is heard, at almost every leap
which it makes, whilst ascending against the upper parts of the trunk of a tree,
or its highest branches. Its notes are clear, loud, and yet rather plaintive.
They are heard at a considerable distance, perhaps half a mile, and resemble the
false high note of a clarionet. They are usually repeated three times in
succession, and may be represented by the monosyllable pait, pait, pait. These
are heard so frequently as to induce me to say that the bird spends few minutes
of the day without uttering them, and this circumstance leads to its
destruction, which is aimed at, not because (as is supposed by some) this
species is a destroyer of trees, but more because it is a beautiful bird, and
its rich scalp attached to the upper mandible forms an ornament for the
war-dress of most of our Indians, or for the shot-pouch of our squatters and
hunters, by all of whom the bird is shot merely for that purpose.
Travellers of all nations are also fond of possessing the upper part of the
head and the bill of the male, and I have frequently remarked, that on a
steamboat's reaching what we call a wooding-place, the strangers were very apt
to pay a quarter of a dollar for two or three heads of this Woodpecker. I have
seen entire belts of Indian chiefs closely ornamented with the tufts and bills
of this species, and have observed that a great value is frequently put upon
them.
The Ivory-billed Woodpecker nestles earlier in spring than any other
species of its tribe. I have observed it boring a hole for that purpose in the
beginning of March. The hole is, I believe, always made in the trunk of a live
tree, generally an ash or a hagberry, and is at a great height. The birds pay
great regard to the particular situation of the tree, and the inclination of its
trunk; first, because they prefer retirement, and again, because they are
anxious to secure the aperture against the access of water during beating rains.
To prevent such a calamity, the hole is generally dug immediately under the
junction of a large branch with the trunk. It is first bored horizontally for a
few inches, then directly downwards, and not in a spiral manner, as some people
have imagined. According to circumstances, this cavity is more or less deep,
being sometimes not more than ten inches, whilst at other times it reaches
nearly three feet downwards into the core of the tree. I have been led to think
that these differences result from the more or less immediate necessity under
which the female may be of depositing her eggs, and again have thought that the
older the Woodpecker is, the deeper does it make its hole. The average diameter
of the different nests which I have examined was about seven inches within,
although the entrance, which is perfectly round, is only just large enough to
admit the bird.
Both birds work most assiduously at this excavation, one waiting outside to
encourage the other, whilst it is engaged in digging, and when the latter is
fatigued, taking its place. I have approached trees whilst these Woodpeckers
were thus busily employed in forming their nest, and by resting my head against
the bark, could easily distinguish every blow given by the bird. I observed
that in two instances, when the Woodpeckers saw me thus at the foot of the tree
in which they were digging their nest, they abandoned it for ever. For the
first brood there are generally six eggs. They are deposited on a few chips at
the bottom of the hole, and are of a pure white colour. The young are seen
creeping out of the hole about a fortnight before they venture to fly to any
other tree. The second brood makes its appearance about the 15th of August.
In Kentucky and Indiana, the Ivory-bills seldom raise more than one brood
in the season. The young are at first of the colour of the female, only that
they want the crest, which, however, grows rapidly, and towards autumn,
particularly in birds of the first breed, is nearly equal to that of the mother.
The males have then a slight line of red on the head, and do not attain their
richness of plumage until spring, or their full size until the second year.
Indeed, even then, a difference is easily observed between them and individuals
which are much older.
The food of this species consists principally of beetles, larvae, and large
grubs. No sooner, however, are the grapes of our forests ripe than they are
eaten by the Ivory-billed Woodpecker with great avidity. I have seen this bird
hang by its claws to the vines, in the position so often assumed by a Titmouse,
and, reaching downwards, help itself to a bunch of grapes with much apparent
pleasure. Persimons are also sought for by them, as soon as the fruit becomes
quite mellow, as are hagberries.
The Ivory-bill is never seen attacking the corn, or the fruit of the
orchards, although it is sometimes observed working upon and chipping off the
bark from the belted trees of the newly-cleared plantations. It seldom comes
near the ground, but prefers at all times the tops of the tallest trees. Should
it, however, discover the half-standing broken shaft of a large dead and rotten
tree, it attacks it in such a manner as nearly to demolish it in the course of a
few days. I have seen the remains of some of these ancient monarchs of our
forests so excavated, and that so singularly, that the tottering fragments of
the trunk appeared to be merely supported by the great pile of chips by which
its base was surrounded. The strength of this Woodpecker is such, that I have
seen it detach pieces of bark seven or eight inches in length at a single blow
of its powerful bill, and by beginning at the top branch of a dead tree, tear
off the bark, to an extent of twenty or thirty feet, in the course of a few
hours, leaping downwards with its body in an upward position, tossing its head
to the right and left, or leaning it against the bark to ascertain the precise
spot where the grubs were concealed, and immediately after renewing its blows
with fresh vigour, all the while sounding its loud notes, as if highly
delighted.
This species generally moves in pairs, after the young have left their
parents. The female is always the most clamorous and the least shy. Their
mutual attachment is, I believe, continued through life. Excepting when digging
a hole for the reception of their eggs, these birds seldom, if ever, attack
living trees, for any other purpose than that of procuring food, in doing which
they destroy the insects that would otherwise prove injurious to the trees.
I have frequently observed the male and female retire to rest for the
night, into the same hole in which they had long before reared their young.
This generally happens a short time after sunset.
When wounded and brought to the ground, the Ivory-bill immediately makes
for the nearest tree, and ascends it with great rapidity and perseverance, until
it reaches the top branches, when it squats and hides, generally with great
effect. Whilst ascending, it moves spirally round the tree, utters its loud
pait, pait, pait, at almost every hop, but becomes silent the moment it reaches
a place where it conceives itself secure. They sometimes cling to the bark with
their claws so firmly, as to remain cramped to the spot for several hours after
death. When taken by the hand, which is rather a hazardous undertaking, they
strike with great violence, and inflict very severe wounds with their bill as
well as claws, which are extremely sharp and strong. On such occasions, this
bird utters a mournful and very piteous cry.
I have only to add to what I have said of the habits and distribution of
this species, that I found it very abundant along the finely wooded margins of
that singular stream, called "Buffalo Bayou," in the Texas, where we procured
several specimens.
IVORY-BILLED WOODPECKER, Picus principalis, Wils. Amer. Orn., vol. iv.p. 20.
PICUS PRINCIPALIS, Bonap. Syn., p. 44.
IVORY-BILLED WOODPECKER, Picus principalis, Nutt. Man., vol. i. p. 564.
IVORY-BILLED WOODPECKER, Picus principalis, Aud. Orn. Biog., vol. i.p. 341; vol. v. p. 525.
Male, 21, 30. Female, 19 1/2, wing 10.
Common in Texas, Louisiana, and along the, Mississippi, to the Ohio. Rare
on the latter, to Henderson. From Florida to North Carolina. Resident.
Adult Male.
Bill long, straight, strong, polyhedral, tapering, compressed and truncated
at the tip; mandibles nearly equal, both nearly straight in their dorsal
outline. Nostrils basal, oval, partly covered by recumbent bristly feathers.
Head large. Neck long and slender. Body robust. Feet rather short, robust;
tarsus strong, scutellate before, scaly on the sides; two toes before and two
behind, the inner hind toe shortest; claws strong, arched, very acute.
Plumage compact, glossy. Feathers of the head elongated and erectile.
Wings large, the third and fourth quills longest. Tail long, graduated, of
twelve tapering stiff feathers worn to a point by being rubbed against the bark
of trees.
Bill of an ivory-white, whence the common name of the bird. Iris bright
yellow. Feet greyish-blue. The general colour of the plumage is black, with
violet reflections, more glossy above. The feathers of the middle and hind part
of the head are of a vivid deep carmine. A broad band of white runs down the
neck and back, on either side, commencing narrow under the ear, and terminating
with the scapulars. The five outer primaries black, the rest white towards the
end, the secondaries wholly white, so that when the wings are closed, the
posterior part of the back seems white, although it is in reality black.
Lateral tail-feathers with a spot of white near the tip of each web.
Length 21 inches, extent of wings 30; bill along the back 2 1/3 along the
gap 3; tarsus 2.
Adult Female.
The female resembles the male in colouring, but wants the vivid patch on
the crest, which is wholly black.
Two of these Woodpeckers, preserved in spirits, have afforded an
opportunity of making the following observations.
The length to end of tail is 19 1/2 inches, to end of wings 16 1/2, to end
of claws 15; wing from flexure 10; tail 9 3/4.
The width of the mouth is 1 inch. The bill, fig. 1, [a b], is much longer than the head, straight, robust, its horny covering of extreme thickness and
solidity. It is broader than high at the base, in the proportion of 1 inch to 8
twelfths. The upper mandible, [a], has its dorsal outline very slightly arched
and deflected, the ridge narrow, the lateral ridge at the base equidistant from
the median ridge and the margin, running parallel with the former, and passing
out at the margin at the distance of 10 twelfths from the tip; the space between
the ridges concave, the margins overlapping and obtuse; the tip wedge-shaped and
truncate. The lower mandible, [b], has the angle of moderate length and width,
the dorsal line ascending and very slightly convex, the ridge narrow, with a
broad groove on each side, beyond which the sides become erect and convex, the
edges very broad, for two-thirds of their length roundish, afterwards flattened,
the tip wedged-shaped and abrupt. The gap-line is almost straight.
The roof of the mouth is somewhat convex: there are upon it two
longitudinal papillate ridges, meeting anteriorly to the palatal slit, whence to
the tip is a median groove, at the anterior extremity of which is a small hole;
the upper mandible is but slightly concave. The posterior aperture of the nares
is oblongo-linear, margined with acute papillae, the space between it and the
ridges also papillate.
The nostrils are oblong, 3 twelfths in length, 1 1/2 twelfths in height,
entirely covered by the bristly reversed feathers. The aperture of the eye is
4 1/2 twelfths in width. That of the ear horizontally oblong, 3 twelfths in
length, and 2 twelfths in height.
The heart is of moderate size, broadly conical, 1 inch 2 twelfths long, 1
inch 1 twelfth in breadth at the base. The liver is very small, the right lobe
much larger than the left, the former being 11 twelfths long and 1 inch broad,
while the latter is 10 1/2 twelfths long and 7 twelfths in breadth. There is no
gall-bladder.
The oesophagus, [a b c], is 6 1/2 inches long, and of the nearly uniform width of 6 twelfths. On entering the thorax, at [a], it curves considerably to the left side, and becomes very muscular; the proventriculus, b c, has a breadth
of 7 1/2 twelfths. The stomach, [c d], is of moderate size, of a broadly
elliptical form, directed a little towards the right, somewhat compressed, 1
inch 2 twelfths long, and of about the same breadth. The muscular fasciculi on
the proventriculus are extremely large. On the stomach also they are of great
size, and the greatest thickness of its muscular coat is 1 1/2 twelfths. This
organ is completely filled with very hard seeds of different kinds, and some
pulpy matter, but without any insects or larvae. Its inner coat is thin, dense,
very tough, nearly smooth, and of a dusky brown colour. The proventricular
glandules, which are very small, form a belt 1 inch in breadth. The intestine,
[d e f g h], is of moderate length and very wide. The duodenum curves at the
distance of 3 1/4 inches. The pylorus is about two-twelfths in width, with an
elevated margin, and allows the untriturated seeds and other refuse to pass into
the intestine, which in some parts is turgid with them. The intestine measures
24 inches in length; its width in the duodenal portion is 3 1/4 twelfths, and so
continues to the length of 12 inches, when it gradually enlarges, so as at the
commencement of the rectum to be 6 twelfths. The rectum itself, [e g h],
continues of that width, and is enlarged into a globular cloaca, [h], 1 1/2
inches in diameter. The whole intestine is more or less filled with pulpy
matter, together with a vast number of grape seeds and others of a much larger
size, but all having a strong shell. Hence it appears that the stomach of this
Woodpecker is not adapted for pounding very hard substances, and that the seeds
of berries and pulpy fruits pass undigested through its intestinal canal. The
same remark applies to all the other species examined. There are no traces of
coeca.
The apparatus, by means of which the tongue of this and other Woodpeckers
is protruded and retracted, is so beautiful a specimen of mechanism, and at the
same time so perfectly simple, although by bungling describers it has been
rendered almost unintelligible, that it may be expedient to present it here in
detail, the more especially that this species, although not that in which it is
exhibited in the highest degree of development or extension, is yet, as being
one of the largest known, peculiarly well adapted for such an examination. Two
figures, therefore, are here introduced.
In Fig. 1 are seen: --The upper and lower mandibles [a b], the tongue [c d],
the terminal barbed portion [c], the fleshy part [d], the orbit and eye [e], the
salivary gland [f], the hyoid bones [g g], the neck [h h], the furcula [i i],
the oesophagus [j j], the trachea [k], its lateral muscles [l l], the
cleido-tracheal [m m].
In Fig. 2 are seen: --The lower mandible b, the salivary glands [f f], the
hyoid bones [g g], the oesophagus [j j j], the trachea [k], the lateral muscles
[l l], the cleido-tracheal [m m], the glosso-laryngeal [n n], the muscles by
which the tongue is exserted [o o].
The bill of this species, Fig. 1, [a b],
measures 3 inches and 2 twelfths
from the angle of the mouth; and the tongue, [c d], which lines in the broad
groove of the lower mandible, reaches to 2 twelfths of the extreme tip, but at
the will of the bird may be exserted so as to extend 3 1/2 inches beyond the
point of the bill. The tongue itself presents the appearance of a slender
fleshy worm-like body, having a middle longitudinal groove on its upper surface,
which is transversely wrinkled, and terminated by a slender tapering bony point,
of which the margins and part of the upper surface are covered with acicular
prickles, which are in some degree moveable and directed backwards, but not
capable of being bent outwards, much less in the direction of the tip of the
tongue. The length of this organ is apparently 2 inches 8 twelfths; but if
measured from the base of the basi-hyal bone, only 1 inch 11 twelfths; its
breadth at the base 2 1/2 twelfths, slightly tapering to the end of its fleshy
part, where it somewhat suddenly contracts, so as to have a breadth of little
more than 1 twelfth. The length of the horny tip is 9 twelfths. The tongue at
the base is entirely destitute of the lobes and papillae which in other birds
give it a sagittate appearance; and there is no uro-hyal bone, which in them
slips into a groove along the front of the thyroid bone of the larynx. The
mouth is of moderate width, its breadth being, as already mentioned, 11
twelfths, it being in this respect very different from that of Flycatchers,
Goatsuckers, Swallows, and such birds as seize on living insects while on wing.
The lower mandible is deeply concave within, wider than the tongue, and covered
with mucous membrane until 1 inch 5 twelfths from the point, beyond which it is
horny, with a median groove, near the commencement of which is a small aperture
for the ducts of the salivary glands. The tongue is capable of being retracted
10 twelfths of an inch from the tip of the mandibles, and is then seen to slide
into a sheath, formed by an induplication or intussusception of the membrane
covering it, and having two froenula of elastic tissue inserted into the angle
of the jaw. Here it may be proper to state, that in birds generally the bony
elements of the tongue are seven, as may be represented by the accompanying diagram, in which the first or upper piece is named the glosso-hyal, the next
the basi-hyal, the third, in the same line, the uro-hyal; the two coming off
from the base of the second piece or basi-hyal are the apo-hyal, to each of
which is appended another, the cerato-hyal. The tongue itself is in no degree
extensile or contractile, but has for its solid basis a very slender basi-hyal
bone, 1 inch 2 1/2 twelfths in length, terminated by a glosso-hyal bone 1/2 inch
in length, but, as already said, has no basal or uro-hyal bone, which, on
account of the unusual extent of its motion, would form an impediment.
From the base of this basi-hyal bone, there proceed backwards and slightly
diverging, two slender apo-hyal bones, 1 inch 1 twelfth in length, each of which
is continuous with an extremely elongated cerato-hyal bone, 4 inches and 1
twelfth in length, 3/4 twelfth in breadth at the commencement, gradually
tapering to a blunt point, convex on its lower surface, concave or channelled on
the upper, passing under and internally of the articulation of the jaw, and
curving upwards along the occiput, until the two meet on the top of the head at
the level of the posterior margin of the orbit, in the median line of the
cranium, which is much depressed, whence they proceed in mutual contact,
inclining slightly to the right side, and terminate a little before the anterior
margin of the orbit, half an inch behind the right nostril, and a quarter of an
inch from the base of the bill. These prolongations of the os hyoides being of
an ossco-cartilaginous texture, are possessed of much elasticity, so as in some
measure to resemble a curved spring.
From near the angle or point of union of the two crura of the lower
mandible internally, there proceeds on each side a slender muscle, [o o], which,
running backwards, comes in contact with the prolongation of the hyoid bone at
the joint between the apo-hyal and cerato-hyal portions, and is thence continued
along the whole extent of the latter, [o g], [o g], running chiefly along its
upper side, but partially enclosing it, and bound to it by a sheath of cellular
tissue, which allows it considerable motion. The bone and muscle are together
enclosed in an extremely delicate, transparent, tenacious sheath, moistened
internally with a serous fluid, and terminating at the end of the bone, where it
is attached by elastic tissue to the cellular substance and periosteum near the
base of the bill. This delicate sheath, perfectly smooth and lubricated on its
inner surface, is on the outer attached by delicate filaments to the dense
cellular tissue which forms a kind of external sheath. It is fixed in its
place, and the hyoid bone with its muscle, g g, slides backwards and forwards in
it.
The entire length from the tip of the tongue, [c], to the tip of each
prolongation of the hyoid bone at e, is 7 inches 2 twelfths. The protrusion of
the tongue is effected by the contraction of the slender muscle above described,
[o], which having a fixed basis in the lower jaw near its angle, and acting upon
the tip of the hyoid bone, which is in this bird situated anteriorly to the eye,
on the forehead, near the base of the upper mandible at [c], causes the hyoid
bone to glide within its sheath until its tip has moved backwards over the
forehead, the crown, and occiput, and then advanced forwards until beneath the
articulation of the lower jaw, thus traversing a space of 3 1/2 inches; so that
the tongue is protruded to 3 inches and 4 twelfths beyond the tip of the bill.
When the muscle is relaxed, the parts regain their ordinary position by the aid
of the elasticity of the prolongations of the hyoid bones, and the action of
another pair of muscles, to be presently described.
The tongue, [d], is covered externally with a dense sheath of fibrous
tissue. On its lower surface is seen on each side a very slender muscle,
commencing at the extremity of the glosso-hyal bone, and running along the whole
length of the basi-hyal bone, as well as of the apo-hyal, to be inserted into
the cerato-hyal, at the distance of one inch from its base, on the outer edge.
The action of this muscle, which has a strong tendon in its whole length, is to
bend the tip of the tongue downwards, or to move the horn of the hyoid bone
outwards. It may be called the glosso-hyal. It has another tendon running
parallel to that mentioned, along its upper edge, of which the action must be to
bend the tongue upwards upon the apo-hyal. Besides these muscles, there is
another pair, forming the greater part of the fleshy portion of the tongue.
They commence at the tip of the basi-hyal bone, or at d, proceed along the upper
surface of the tongue, and, after running a course of 2 3/4 inches, pass along
the anterior surface of the thyroid bone, wind along its edge, and are inserted
near the middle surface of the trachea, about its tenth ring. The action of
these muscles, alluded to at the end of the last paragraph, and marked [n n], is
to retract the tongue, when extended, as well as to pull forward the larynx.
Another pair of very slender muscles, [m m], commence upon the edge of the
thyroid bone externally of those last described, separate immediately from the
trachea, pass directly down the neck in front, under the subcutaneous muscle and
skin, to which they are firmly attached by cellular tissue, and are inserted
into the furcular bone about the middle of its length. These muscles, the
cleido-tracheales, are not peculiar to Woodpeckers, and have nothing particular
to do with the movements of the tongue in those birds.
Parallel to the lower edge of the jaw, and extending from 4 twelfths
anteriorly to its articulation to the junction of its crura, is, on each side,
an elongated salivary gland, [f f], attached to the jaw by cellular tissue. It
is of a yellowish colour, internally parenchymatous, and sends off a duct, which
enters the mouth by the aperture already mentioned, at the commencement of the
groove in the horny part of the lower mandible. The fluid which it secretes is
a glairy mucus, of a whitish colour, which being poured forth around the tip of
the tongue covers it with a glutinous substance well adapted for causing the
adhesion of any small body to it.
The Ivory-billed Woodpecker, then, having discovered an insect or larva in
a chink of the bark, is enabled by suddenly protruding its tongue, covered with
thick mucus, and having a strong slender sharp point furnished with small
reversed prickles, to seize it and draw it into the mouth. These prickles are
of special use in drawing from its retreat in the wood those. large larvae,
often two or three inches in length;, but it does not appear probable that the
bristly point is ever used to transfix an object, otherwise how should the
object be again set free, without tearing off the prickles, which are extremely
delicate and not capable of being bent in every direction?
The trachea, [k k], is 5 inches 4 twelfths in length, considerably
flattened, nearly of the uniform breadth of 3 twelfths throughout. The aperture
of the glottis is 4 twelfths long, with a posterior flap of several series of
papillae. The rings of the trachea are very strong, firmly ossified, 92 in
number. At the upper part 3 are incomplete; the last entire ring is very broad
and bipartite, and there are 2 additional dimidiate rings. The bronchi are
short, of 12 half rings. The lateral or contractor muscles, [l l], commence in
front, at the base of the thyroid bone, diverge, presently become lateral, and
thus proceed until 4 1/2 twelfths from the extremity, when they terminate partly
in the sterno-tracheal, but also send down a very thin slip, which is inserted
on the first dimidiate ring.
The explanation of the mechanism by which the tongue is protruded as above
given, differs materially from any of those to be found in English works at
least, in some of which there is a very unnecessary prolixity as well as
ambiguity. It does not appear that hitherto the real sheath in which the horns
of the hyoid bone, with its muscle, move, has been observed, and the two very
slender muscles which run from the sides of the thyroid bone to the furcula, are
common to almost all birds, although they have been supposed to be peculiar to
Woodpeckers.
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