Alfred Charles Smith.

The birds of Wiltshire. Comprising all the periodical and occasional visitants, as well as those which are indigenous to the county online

. (page 6 of 53)
Online LibraryAlfred Charles SmithThe birds of Wiltshire. Comprising all the periodical and occasional visitants, as well as those which are indigenous to the county → online text (page 6 of 53)
Font size
QR-code for this ebook


of the thigh have caused very general errors on the subject), they
differ from one another in many ways ; thus, some are extremely
long, others are exceedingly short; some are quite bare of
feathers, others are entirely clothed with them ; some are plated,
as it were, with scales, others are smooth ; some are thick and



42 Introduction.

strong, others are light and delicate ; but all harmonize exactly
with the feet with which they terminate, and these present still
greater points of variety than the legs. The foot of a bird,
unlike that of a quadruped, is never composed of more than four
toes ; this is the most general number, and of these the first is
usually directed backwards, though in some cases the fourth is
also associated with it. There are other families which have but
three toes, and in that case all of them are directed forwards, the
first or hind toe being the one deficient. Again, there are birds
which have but two toes ; but as none of these last occur in this
country, we need not stop to consider their peculiarity. And
again, the toe may be united by a membrane, and that either
entirely, or in part ; or they may be wholly unconnected ; but
they are always terminated with claws, which present the varieties
of long and short, straight and curved, sharp and blunt ; but
these, together with many other points of difference, and the
reasons of them, and the suitability of the exact form of foot
with which every bird is provided, we shall more clearly see as
we go on to consider the orders and families in rotation.

The ' Birds of Prey ' present a great general similarity in the
formation of the foot. It is always strong and muscular, fur-
nished with four powerful toes, and armed with claws more or
less hooked, and often of very formidable size, strength, and
sharpness. In the family of vultures the talons are not so much
displayed, as the habits of these ignoble birds require no weapon
for striking a blow to obtain their food, and no powers of grasping
for bearing it away in their feet to their young. Content with the
putrid carcase of some fallen animal, these unclean birds stuff
themselves with carrion, and carrying it in their craw to their
nests, there disgorge the unsavoury mess. But the falcons have
by their own prowess to secure their living prey, and so, in addi-
tion to very powerful limbs and great muscular strength, are
provided with sharp and generally much curved claws, enabling
them to strike down and hold securely the victims they have
seized. Like the carnivorous quadrupeds, these rapacious birds
can pounce so fiercely and with such exceeding violence with



The Feet of Birds. 43

their formidable talons, as generally at one blow to disable their
prey. It is invariably the claw of the hind toe by which this
severe stroke is effected, and for this purpose the beak is never
used at all, though many people have erroneous impressions to
the contrary. Hushing down with the velocity of lightning, and
with closed pinions, the falcon makes its deadly swoop from
above on the selected prey, and striking with the hind toe in
darting past, inflicts the deadly wound in a most masterly
manner, seldom missing its aim or failing in the stroke. Some-
times, too, the back of the unfortunate victim is seen to be deeply
scored throughout its whole length, while not unfrequently the
skull is completely riven and the brains dashed out by the
amazing impetus of the blow. But should the aim be by some
mischance incorrect, then rising again and sailing round in
circles, and so getting higher and higher at every turn, the falcon
again prepares for a charge, while the unhappy bird whose life is
so endangered seems instinctively to know wherein its best
chance of escape lies, and perceiving that an attack can only be
made from above, soars as high as its strength enables it.
Seldom, however, does the manoeuvre succeed, and the second
swoop of the aggressor rarely fails to send the quarry headlong
and lifeless to the ground. For inflicting such a wound, no more
perfect instrument can be conceived than the falcon's foot, so
strong, hard, and muscular, with claws so sharp, powerful, and
curved. With these weapons they can not only provide them-
selves food, but with the same instruments can grasp and carry
it off to their eyries, though it be of considerable weight. The
nature of the prey, too, so obtained and borne away varies not a
little, according to the genera comprising this extensive family ;
for fish, flesh, and fowl are all attacked by these rapacious birds.
The eagles can master a full-sized hare or a lamb; the osprey
will plunge into the river, and emerge again with a quivering
salmon firmly clutched in its talons ; the true falcons, the hawks,
the buzzards, and the harriers, content themselves with the
smaller birds and quadrupeds, and some species vary their diet
with reptiles ; but they all seize and bear off their prey with



44 Introduction.

their feet. The third and last family of the Raptores, viz., the
owls, hunting in the dusk of evening and the gray twilight of
morning, adopt a different course from their diurnal brethren of
prey ; stealing on noiseless wing round the enclosures and over
the meadows, they drop suddenly and without warning of their
approach on the mouse or other victim, which they bear away in
their feet. Their legs and toes are usually covered with downy
feathers up to the claws, assisting them in their silent move-
ments, and strong enough to carry off any victim which they
may seize. In all these carnivorous birds, can anything more
perfect be conceived than the feet with which they 'are provided,
more fitted to their respective requirements, more thoroughly
adapted to their wants ?

The second order of birds, the ' Perchers,' brings before us
quite a different form of foot, but one no less applicable to the
habits of the species which compose it ; nay, by many the form
of foot herein displayed is considered the most perfect, and
perhaps if any degrees of excellence can exist, where all are
exactly fitted to their respective uses, the mechanism of the
foot of the ' Insessores' may strike us with the greatest admira-
tion. The tarsus of all these birds is usually bare of feathers,
and the general character of the leg and foot is slight and
slender ; the number of toes is invariably four, the hind toe
being always present : in some species the claws are very long,
but in general they as well as the toes are short, and thus best
formed for perching. When, then, we look at these light and
delicate legs and feet, 'the skin reduced,' as Buffonwell describes
it, ' till it is nothing more than a bony needle/ and then observe
the size and weight of the body they have to support, is it not
astonishing with what ease and steadiness a bird can perch upon
a bough, and balance and uphold itself in that position, even in
a high wind ? is it not marvellous how, with the head reposing
under the wing and one leg drawn up under the body, it is
entirely supported on the other; and resting on so slight a
fulcrum, falls asleep, without the least danger of losing its
balance ? It is the admirable formation of these delicate



The Feet of Birds. 45

members that enables the feathered race to rest with ease in a
position in which other animals could not support themselves
for a minute ; and of which formation the true perchers afford
so excellent an example. The natural position of a bird's toes is
not, as with men's fingers, stretched out and open, but the very
reverse ; it requires an effort in the bird to spread open its toes,
just as it does in a man to close his fingers. Hence, when it
rises on the wing and flies through the air, the foot is doubled
up under the body, and the toes immediately contract, and only
unbend again when about to seize the bough of a tree ; hence,
again, when it perches on a spray, the toes, previously opened
for the purpose, grasp it by their natural flexion, and firmly
clasp the support on which they have alighted. This is a very
excellent adaptation of peculiar structure to the required end,
but in addition to this there is a most admirable piece of internal
mechanism, which I cannot better describe than in the words of
Bishop Stanley : ' Connected with the thigh-bones and leg, a cefc
of muscles run down to the very extremity of the toes, so con-
trived and placed that, when by pressure downwards the limb
bends, these fine muscles are pulled in, and therefore contract
the toes, thus making them grasp more firmly whatever the bird
is resting upon ; just as if a set of fine strings ran over pulleys to
certain hooks, and were acted upon at the other end by a weight
or pressure, and thereby made to draw in the hooks.' Such,
then, is the wonderful power given to perching birds, whereby
they can hold themselves securely even in sleep on so slender a
support. This faculty is shared in by the whole order ; but as
the families and genera which compose this extensive division are
so numerous, and obtain their food in such a variety of ways, it
is clear that there must be considerable varieties in the develop-
ment of their feet. The tribes which dwell among the boughs
of trees, now hanging with their heads downwards, now hurry-
ing along the underside of the branch, will require a foot some-
what differently formed from those which run on the ground
and perch on the topmost spray. Still, in so vast a number,
it will be impossible in this place even to touch upon the



46 Introduction.

points in which they vary ; but as throughout the entire order
there is so considerable a similarity of structure in this particular,
it will not be necessary for the due exposition of my subject to
enter into further details upon it. We have said enough to show
how worthy is the construction of their feet to give a name to
the whole order, as Insessores or ' Perchers.'

In the Rasores, or ' Ground-birds,' we shall see a formation of
foot widely differing from both the above orders. These are a
harmless and quiet race, never preying upon other creatures, but
eating berries and grain, and such food as they can find upon
the ground; and they are subject to frequent attacks from
carnivorous birds as well as quadrupeds. Their flesh, too, being
very palatable, man is not the least of their destroyers ; but with
so many enemies from which to escape, their flight is laboured
and heavy, and they are unable to protract it to any great dis-
tance. Providence, however, which leaves no creature without
some means of defence, has provided for the ground-birds a
suitable remedy in their remarkable powers of running; for
this end such feet as those which I have shown to belong to the
above-named divisions would be little adapted ; in lieu of which
they have frequently but three toes, the hind one being
altogether omitted, or, if present, it is always very small and
considerably elevated. All the toes are very short, and excel-
lently adapted for running, not only for swiftness (though that
is often very great), but also for long continuance and protracted
exertion ; moreover, they are provided with limbs of great
muscular development, as well as with short and blunt claws :
thus the members of this order, when alarmed, run from the
supposed danger at their utmost speed, and endeavour to conceal
themselves under the thickest cover at hand; and it is only
when hard pressed, and other means of escape fail, that they rise
on the wing with considerable exertion, and fly heavily away.

We come now to the two orders of Water-birds, and in each
of these we shall see the feet and legs adapted precisely to the
habits of their possessors. The Grallatores, or " Waders,' first
claim our notice. They seem to be a connecting link between



The Feet of Birds. 47

the true land and water birds, partaking somewhat of the nature
of each. 'Generally incapable of swimming, and therefore unable
to go into deep water, they are formed for passing a great
portion of their time on land ; but yet, as all their food must be
procured from the water, or from wet and marshy spots, they
haunt the vicinity of lakes or streams, or the seashore ; and, as
a combination of both elements, delight in fens and swamps,
where they can wade about, or stand motionless, fishing for prey.
For such an amphibious nature, and such dabbling habits, how
well fitted are their legs and feet ; the tarsus of extreme length ;
the tibia frequently bare of feathers to a considerable distance
above the tarsal joint ; the toes always divided, but very long,
and usually slender, and of which the third and fourth are
frequently united by a membrane ; all present admirable facilities
to these birds for indulging their wading and fishing propen-
sities ; for as the great length of leg suffers them to walk in
water of some depth, without wetting their plumage, so the
wide- spreading form of their foot enables them to stand and run
on soft and doubtful ground, without sinking in. Thus, like the
stilts and flat boards on which the fenmen of Lincolnshire have
for ages been accustomed to traverse their swamps, so the long
legs and spreading feet of the waders are the instruments with
which nature has provided them for the same purpose.

Widely different from the last described, but no less perfect,
and no less adapted to their peculiar requirements, are the feet
of the Natatores, or ' Swimmers ;' these dwell in and on the
water ; at one time on the surface, floating over the waves, at
another far below, diving for food or for safety. Many species
belonging to this order are quite incapable of walking on land,
and are but scantily provided with wings of much avail for
prolonged flight ; their chief means then of moving about are
by swimming and diving, which they do to perfection. All the
divers and auks present a grotesque and clumsy appearance on
shore : even the ducks cut but a sorry figure as they waddle
over the grass ; but place them in their own element, let them
once reach the water, and their awkwardness becomes elegance,



48 Introduction.

their clumsiness is transformed into the greatest activity. To
enable them to move about on the water with such ease and
such celerity, they are supplied with legs and feet very much
resembling the paddles used in Indian canoes : their thighs are
placed very far back, in some instances almost at their tails ;
their legs are very flat and extremely thin, like the blade of an
oar ; their feet are broad and large, and completely webbed, the
toes connected together with membranes up to the nails ; with
these they strike the water with considerable force, and thus
their bodies are impelled forwards with speed ; and as the boat-
man, in rowing, feathers his oar after each successive stroke,
and in order to offer as small a surface as possible to the resist-
ance of the air and water, presents the thin knife-like edge of
the blade, while he draws it back for the next stroke, but while
pulling it through the water presents the broad blade as a means
of obtaining a good purchase for his pull just so is it with the
feet and legs of the swimming birds ; at every stroke the broad flat
leg and the expanded webbed foot give a hearty thrust ; but in
withdrawing them again, preparatory to repeating the thrust, the
thin edge of the leg is presented to the water, and the toes are
drawn together, and closely folded up, presenting as little resist-
ance as possible, till they are spread out again for the next
stroke. With these admirable provisions for moving at will on
the waves all the swimmers are supplied, but as some families are
more expert in the water, and less able to leave it for the shore
or the air than others, there are considerable variations in the
exact formations of their feet : thus, some have only three toes ;
others have four, but frequently three only are webbed, the
fourth remaining free, and articulated high up on the tarsus;
others again, have a pendant lobe or membrane, depending from
the hind toe, while some have all four toes completely webbed
together. According to these different formations, so their
powers of swimming and diving are increased or lessened ; but
all enjoy those faculties to a considerable extent.

Such, then, are the general characters of the feet, as applicable
to the five orders. Though those of certain individual species



The Feet of Birds. 49

will in some cases be seen to vary from this description, it will
on the whole be found to be typical of the division to which it
refers. Thus we see the birds of prey armed with feet and
claws which form the most powerful weapons for striking down
and carrying off their victims. The perchers provided with so
exquisite a piece of mechanism as to enable them to seize,
balance, and support themselves on a branch with ease. The
ground-birds furnished with limbs so strong, muscles so powerful,
and feet so adapted for the purpose, as to make them seek safety
in running when beset by foes. The waders, though often unable
to swim, raised high out of the water in which they seek their
food by the length of their legs, and enabled by their spreading
toes to run lightly over water-plants and the softest mud without
danger of sinking in. The swimmers supplied with feet and
legs serving them for oars and rudders, whereby to impel for-
wards their bodies on the waves, or to seek their food far below
the surface of the water. These are all instruments so exactly
and so perfectly adapted to their respective uses, that we can
conceive nothing more applicable ; and they are plain and easy
marks to us for ascertaining the general habits and classified
position of any bird we observe. Our examination of the subject
might well stop here ; but, before concluding this paper, I would
call attention to a few remarkable instances of structure in regard
to the feet, as displayed by some particular species.

The Osprey alone, of all the family Falconidce, lives entirely
upon fish, and the nature of its prey being therefore different
from that of its congeners, it requires and is furnished with feet
peculiarly fitted for seizing and holding securely the slippery
denizens of the deep. In the first place, in lieu of the long
feathers which commonly clothe the thighs of the falcon race,
short ones are substituted, which leave more freedom for action
in the water ; then the outer toe is reversible, and can at pleasure
be turned backwards, so that, as Yarrell tells us, it is the custom
of the bird to < seize the prey across the body, placing the inner
and outer toes at right angles with the middle and hind toes ;
and, digging in the claws, to hold the fish most firmly by four

4



50 Introduction.

opposite points.' Moreover, the soles of its feet are remarkably
rough, and covered with protuberances, while the talons are very
much curved, sharp, and strong, that of the outer toe being the
largest, which is contrary to the usual custom ; and all these
peculiarities tend to the holding with greater security the slimy
victims on which it lives.

The Nightjar, which feeds at twilight, presents another very
peculiar formation of foot. This is small and weak in proportion
to the size of the bird, but is remarkable for the claw of the
middle toe, which is particularly long and serrated, or pectinated,
on its inner edge, and resembles a comb with seven or eight
teeth. Now the food of the nightjar consists of moths, but
especially of fern-chaffers, beetles, and such late flying insects,
the legs of which are often terminated with hooked claws, to
detach which from the wide gaping mouth, and from the bristles
with which the upper mandible of the beak is fringed, this comb-
like claw is probably appended to the foot ; I say probably, for
much difference of opinion has existed with reference to its use.
Gilbert White, and others after him, thought they could perceive
the bird put out its short leg while on the wing and deliver
something into its mouth, and thus accounted for its use, that it
enabled the bird to hold more securely in its foot the insect it
had caught ; but for such a purpose it certainly seems but very
ill calculated.

The Swift furnishes another instance of remarkable structure
of foot. As it passes the livelong day in unceasing and rapid
flight, it requires no great development of leg and foot ; thus the
tarsus is exceedingly short and thick, so short as to render the
bird incapable of rising from a flat surface, and therefore it never
alights on the ground. For rest and for incubation it retires to
the eaves of steeples and towers, to the perpendicular walls of
which, and to the face of cliffs, its foot is well adapted to cling ;
thus it consists of four toes, all of which are directed forwards,
and are armed with very hooked claws, and quite divided, and
which give it the appearance of belonging to a quadruped rather
than a bird.



The Feet of Birds. 51

The Woodpeckers are also furnished with feet most suitable to
their climbing habits. Each foot is provided with four toes,
arranged in pairs, two directed forwards and two backwards ;
these afford an immense support, and as they are very strong and
terminate with hooked claws, it may be conceived what useful
instruments they must be to birds whose lives are passed in
climbing about the trunks and branches of trees ; indeed, very
similar in form are they to the iron crampions which the Swiss
chamois-hunter affixes to the soles of his feet when about to
scale the precipices of the Alps and climb among the dangerous
chasms of the glacier.

Again, the Avocet is provided with feet of singular construc-
tion. This bird is a wader in every sense, deriving its food from
the softest mud at the estuaries of rivers, to support it on which
no ordinary feet would suffice ; we see the toes, therefore, united
for a considerable part of their length by a concave membrane,
not wholly webbed, for the bird is incapable of swimming to any
distance, but semi-palmated, and connected far more than those
of any other species in the order ; the tarsus, too, is long and
slender: the tibia naked for two-thirds of its entire length, so
that it can wade into water of considerable depth, in search of
food.

No less singular in the appearance of its legs and feet is the
Black-winged Stilt, or Long-legged Plover; either name at
once points to the remarkable and apparently disproportionate
length of its legs, on which its body seems raised up above the
water, as if on stilts. It is almost needless to add that this bird,
too, obtains its food by wading in muddy creeks and shallows on
the shore.

The Coots and Phalaropes, which compose jthe small family
lobe-footed, claim our attention last. I have before alluded to
them as the connecting-link between the true waders and
swimmers, and their feet certainly present a peculiarity, par-
taking of the form which is characteristic of both those orders.
Thus, though the toes are not wholly united by a connecting
membrane, yet they are furnished laterally with it to such a

42



52 Introduction.

degree as almost to answer the same purpose. This membrane,
so extended, forms what are technically called ' rounded lobes ;'
hence their family name ; and with such curious feet these birds
seem as active on land as they are in the water running, walk-
ing, even climbing trees, wading, swimming, and diving with the

greatest ease.

Thus the feet of birds, though with a certain general similarity
of structure, differ one from another in a variety of ways. As
their habits and manner of life vary exceedingly, and as they are
constituted to occupy no less than three elements earth, air,
and water we see every individual furnished with such' means
of locomotion as best suit its own particular sphere. Had the
lordly eagle, pouncing on its quarry, but the foot of a partridge
wherewith to inflict his wound, starvation must be his lot ; or
had the pheasant to run from danger with the feet of the diver,
slight, indeed, would be its chance of escape. The heron, if sup-
ported on the legs of a hawk, would certainly be drowned in
fishing for food. The rook would rest but insecurely on the
bough of the elm, if it clasped its support only with the feet of
the plover. But now, supplied with such instruments as their
respective pursuits require, all are enabled with ease to obey
their own peculiar instincts, and fill the place allotted to them in
nature.

I have now brought to a conclusion my preliminary remarks on
the general structure, and a few of the more prominent attributes
of the feathered race ; and perhaps I ought to apologise to my
readers for the length to which these remarks have run. I trust



Online LibraryAlfred Charles SmithThe birds of Wiltshire. Comprising all the periodical and occasional visitants, as well as those which are indigenous to the county → online text (page 6 of 53)