[1] "To feast" is simply to keep a festum or festival. The etymology
of the word is uncertain; but probably it has no connexion with the
Gr. [Greek: hestian].
[2] See Spencer, _Principles of Sociology_, i. 170, 280, 306.
[3] Haug, _Parsis_, 224, 225.
[4] "May the heavens, the waters, the firmament, be kind to us; may
the lord of the field be gracious to us.... May the oxen (draw)
happily, the men labour happily; may the traces bind happily, wield
the goad happily" (Wilson's translation, iii. 224).
[5] See Haug's _Aitareya-brahmanam of the Rig-Veda_; Max Muller's
_Chips from a German Workshop_, i. 115.
[6] Visperad. See Haug, _Parsis_, 192; Richardson's _Dissertation on
the Language, &c., of Eastern Nations_, p. 184; Morier's _Journey
through Persia_.
[7] Plutarch, _De Iside et Osiride_; Macrobius, _Saturnalia_, i. 21.
[8] In this month the anniversaries of the battle of Marathon, and of
the downfall of the thirty tyrants, were also publicly celebrated.
[9] See Schoemann, _Griechische Altertumer_, ii. 439 seq.; Mommsen
_Heortologie_.
[10] _Feriae privatae_, such as anniversaries of births, deaths, and
the like, were observed by separate clans, families or individuals.
[11] In the "parallel" passages, there is considerable variety in the
designation and arrangement of these feasts. While Ex. xii.
approximates most closely to Lev. xxiii. and Num. xxviii., Ex. xxiii.
has stronger affinities with Deut. xvi. The relations of these
passages are largely discussed by Graf, _Die geschichtlichen Bucher
des A. T._, pp. 34-41, and by other recent critics.
[12] On the whole subject of Jewish festivals see Reland, _Antiq.
Hebr._; Knobel, _Leviticus_ (c. 23); George, _Die judischen Feste_;
Edersheim, _The Temple; its Ministry and Services_; Ewald,
_Altertumer des Volkes Israel_; articles in Bible dictionaries.
[13] As, at a later period (601), Gregory the Great instructed his
Anglo-Saxon missionaries so to Christianize the temples, festivals,
&c., of the heathen "ut durae mentes gradibus vel passibus, non autem
saltibus, eleventur."
[14] Manumission, however, was lawful on any day.
FEATHER (O. Eng. _fether_, Ger. _Feder_, from an Indo-European root seen
also in Gr. [Greek: pteron], and [Greek: petesthai], to fly), a horny
outgrowth of the skin of birds homologous with the scale of the reptile.
The body-covering of birds is, without exception, comprised of feathers,
and by this character alone birds may be distinguished from all other
animals.
The most perfect form of feather is made up of a long, tapering rod,
fringed on either side, for the greater part of its length, by a
secondary series of slender and tapering rods forming a more or less
acute angle with the central axis. This fringe is known as the
_vexillum_ or "vane" (fig. 1 a). The central axis is divisible into two
distinct parts,--a hollow, cylindrical, transparent _calamus_, or
"quill," the base of which is inserted into the skin, and a solid,
quadrangular _rhachis_ or "shaft" which supports the vane. At the lower
end of the quill is a small hole--the lower _umbilicus_--through which
the nutritive pulp passes during the growth of the feather: while at the
upper end, where it passes into the shaft, a similar hole will be
found,--the upper _umbilicus_--and from this the last remains of the
capsules which contained the nutritive pulp may sometimes be seen
protruding. If the quill is cut open a series of these capsules will be
found fitting one into the other throughout the whole length of the
tubular chamber.
[Illustration: Fig. 1.--Diagrams of Feather-Barbs.
a, Outline of a feather showing the relation of the barbs and barbules
to the central axis or shaft.
b, Section across two of the barbs shown in a, highly magnified.
c, Two barbules of the posterior series--seen only in cross-section in
b.
d, A barbule of the anterior series.
e, Section across the base of three anterior barbules showing
attachment to barb.
f, A portion of the hooklet of the anterior series showing the method
of interlocking with the barbules of the posterior series.]
The rods comprising the lateral fringe, or vane, are known as the _rami_
or the "barbs," and will be found, on microscopic examination, to be
lath-shaped and to taper to a point. Further, each barb supports a
double series of smaller outgrowths known as the _radii_, or "barbules";
so that each barb may be likened to a feather in miniature. These
"barbules," however, differ markedly in structure on the two sides of
the barb, those pointing towards the tip of the feather--the "anterior
barbules"--being ribbon-shaped from the base outwards for about half
their length, when they become cut up to form a series of long and very
delicate hooklets (fig. 1 d). On the opposite side of the barb the
barbules are also ribbon-shaped for about half their length, but the
ribbon is curved trough-fashion, so that the whole series of posterior
barbules forms a number of deep valleys, and into these the hooklets are
thrust so as to catch hold of the upper edges of the troughs, which are
set so that the upper edge is towards the upper, and the lower edge
towards the under surface of the feather. The manner in which this
beautiful mechanism works may be seen in fig. 1 b.
In one of the primary or "quill" feathers of the wing of a crane, each
barb of the inner side of the vane was found to bear about 600 pairs of
barbules, which would make about 800,000 barbules for the inner web of
the vane alone, or more than a million for the whole feather (H.F.
Gadow). It is to the agency of these hooklets alone that the
closely-knit, elastic vanes of the flight feathers and the body feathers
are due. Where these hooklets are wanting the barbs do not adhere
together, resulting in a loose "discontinuous" vane such as, for
example, is found in the plumes of the ostrich.
Many feathers, in addition to the main axis, bear a second, generally
much shorter axis, supporting a loose discontinuous vane; this shorter
branch is known as the "aftershaft" and arises from the under surface of
the feather. Only in the cassowary and emu among adult birds is the
aftershaft as large as the main shaft.
There are several different kinds of feathers--contour feathers,
semiplumes, down-feathers, filoplumes and powder-down. Contour feathers,
as their name implies, are those which form the contour or outline of
the body, and are all that can generally be seen. Those which form the
"flight feathers" of the wing, and the tail feathers, are the most
perfectly developed. Semiplumes are degenerate contour feathers. The
down-feathers are generally completely hidden by the contour feathers:
they form in many birds, such as gulls and ducks, a thick underclothing
comparable to the under-fur of mammals such as the seals. In all cases
they are of a loose, soft, "fluffy" structure, the barbs being of great
length and slenderness, while the barbules are often long and provided
with knob-like thickenings answering to the hooklets of the more
perfectly developed contour feathers; these thickenings help to "felt"
the separate down-feathers together, the barbs of one down-feather
interlocking with those of its neighbour. Down-feathers differ from
semiplumes both in their relation to contour feathers and in that they
do not possess a main axis, all the barbs arising from a common centre.
Filoplumes are degenerate structures having a superficial resemblance to
hairs, but they always bear a minute vane at the tip. They occur in all
birds, in clusters of varying number, about the bases of contour
feathers. In some birds they attain a great length, and may project
beyond the contour feathers, sometimes forming conspicuous white
patches, as for example in the necks of cormorants. In their early
stages of development they often possess a large aftershaft made up of a
number of barbs, but these quickly disappear, leaving only the
degenerate main shaft. The eyelashes and bristles round the mouth found
in many birds appear to be akin to filoplumes.
Powder-down feathers are degenerate down-feathers which appear to
secrete a dry, waxy kind of powder. This powder rapidly disintegrates
and becomes distributed over the plumage, adding thereto a quite
peculiar bloom. In birds of the heron tribe powder-down feathers have
reached a high degree of development, forming large patches in the
breast and thighs, while in some hawks, and in the parrots, these
mysterious feathers are scattered singly over the greater part of the
body.
Nestling down.
The nature of the covering of nestling birds is of a more complex
character than has hitherto been suspected. The majority of young birds,
as is well known, either emerge from the egg clothed in down-feathers,
or they develop these within a day or two afterwards. But this covering,
though superficially similar in all, may, as a matter of fact, differ
widely in its constitution, even in closely related forms, while only in
a very few species can the complete history of these feathers be made
out.
The brown or tawny owl (_Syrnium aluco_) is one of these. At hatching,
the young of this species is thickly clad in white, woolly
down-feathers, of the character known as umbelliform--that is to say,
the central axis or main shaft is wanting, so that the barbs all start
from a common centre. These feathers occupy the position of the
ultimate contour feathers. They are shortly replaced by a second
down-like covering, superficially resembling, and generally regarded as,
true down. But they differ in that their barbs spring from a central
axis as in typical contour feathers. Feathers of this last description
indeed have now made their appearance in the shape of the "flight" or
quill feathers (_remiges_) and of the tail feathers. This plumage is
worn until the autumn, when the downy feathers give place to the
characteristic adult plumage. The down feathers which appear at
hatching-time are known as _pre-pennae_, or _pre-plumulae_, as the case
may be; the first generation of pre-pennae, in the case of the tawny owl
for example, is made up of _protoptyles_, while the succeeding plumage
is made up of _mesoptyles_, and these in turn give place to the
_teleoptyles_ or adult feathers. The two forms of nestling
plumage--pre-pennae and pre-plumulae--may be collectively called
"neossoptyles," a term coined by H.F. Gadow to distinguish the plumage
of the nestling from that of the adult--the "teleoptyle" plumage.
As a rule the nestling develops but one of these generations of
neossoptyles, and this generally answers to the mesoptyle plumage,
though this is of a degenerate type. In some birds, as in the Megapodes,
the "protoptyle" or first of these two generations of pre-pennae is
developed and shed while the chick is yet in the shell, so that at
hatching the mesoptyle plumage is well developed. But in the majority of
birds, probably, the mesoptyle plumage only is developed, while the
earlier, and apparently more degenerate, dress is suppressed. In the
penguins both of these nestling plumages are developed, but the
mesoptyle dress has degenerated so that umbelliform feathers now take
the place of feathers having a central axis.
The Anatidae show traces of the earlier, first generation of feathers in
one or two species only, e.g. _Cloephaga rubidiceps_. In all the
remaining species mesoptyles only occur. And this is true also of the
game-birds. In both the Tinamous, the duck-tribe and the game-birds this
mesoptyle plumage shows, in different species, every gradation between
feathers having a well-developed main shaft and aftershaft, and those
which are mere umbelliform tufts.
As development proceeds and the contour feathers make their appearance
they thrust the mesoptyle feathers out of their follicles--the pockets
in the skin in which they were rooted--and these will often be found
adhering to the tips of the contour feathers for many weeks after the
bird has left the nest. This occurs because the development of the
contour feather begins before that of the mesoptyles has completed.
The plumage in nestling birds is still further complicated by the fact
that it may be almost, or entirely, composed of pre-plumulae; that is to
say, of down-feathers which are later succeeded by adult
_down-feathers_. This is the case among the accipitrine birds for
example, and thereby it differs entirely from that of the owls, which
develop neither pre-plumulae nor adult down. The cormorants are, so far
as is known, the only birds which have a nestling plumage composed
entirely of pre-plumulae.
The colours of feathers.
In variety and brilliancy the colours of birds are not surpassed by
those of any other group of animals. Yet the pigments to which these
colours are due are but few in number, while a large number of the most
resplendent hues are produced by structural peculiarities of the
colourless horny surface of the feathers, and hence are known as
subjective or optical colours.
The principal colour pigments are (a) _melanin pigments_, derived
possibly from the haemoglobin of the blood, but more probably from the
blood plasma, and (b) _lipochrome_ or "fat" pigments, which are regarded
as reserve products; though in the case of birds it is exceedingly
doubtful whether they have this significance.
The melanin pigments (_zoomelanin_) occur in the form of granules and
give rise to the black, brown and grey tones; or they may combine with
those of the lipochrome series.
The lipochrome pigments (_zoonerythrin_ and _zooxanthin_) tend to be
diffused throughout the substance of the feather, and give rise
respectively to the red and yellow colours.
In addition to these must be reckoned _turacin_, a reddish-purple
pigment consisting of the same elements as zoomelanin, but remarkable
for the fact that it contains from 5 to 8% of copper, which can be
extracted by a weak alkaline solution, such as ammonia, and with the
addition of acetic acid it can be filtered off as a metallic red or blue
powder. The presence of metallic copper is indicated by the green flame
of these red feathers when burnt. Turacin was discovered by Sir A.H.
Church in the quill-feathers of the wings of Touracoes or "plantain
eaters." These feathers, he showed, lose their colour after they have
become wet, but regain it on drying. But turacin is not, as was
supposed, confined to the feathers of the plantain eaters, since it has
been obtained from a cuckoo, _Dasylophus superciliosus_.
What effect food may have on colour in birds in a wild state we have no
means of knowing, but it is significant that flamingoes and linnets in
confinement never regain their bright hues after their first moult in
captivity. If cayenne pepper be mixed with the food of certain strains
of canaries, from the time the birds are hatched onwards, the yellow
colour of the feathers becomes intensified, till it takes on a deep
orange hue. Bullfinches, if fed on hemp-seed, turn black. According to
Darwin, the natives of the Amazonian region feed the common green parrot
on the fat of large Siluroid fishes, and as a result the feathers become
beautifully variegated with red and yellow. Similarly, in the Malay
Archipelago, the natives of Gilolo change the colours of another parrot.
With but rare exceptions bright colours are confined to the exposed
portions of the plumage, but in some of the Bustards the down is of a
bright pink colour.
Structural colours.
Structural colours include all metallic or prismatic colours, blue,
green, white, some yellows, and, in part, glossy black. In metallic
feathers the radii (barbules) are modified in various ways, frequently
to form flattened, overlapping plates or tiles, while the surfaces of
the plates are either smooth, finely striated or pitted. But, save only
in the case of white feathers, beneath this colourless, glazed outer
coat there is always a layer of pigment.
The only green pigment known to occur in feathers is _turacoverdin_,
found in the feathers of the plantain eaters; it contains a relatively
large amount of iron, but no copper. In all other cases the green colour
of feathers is due to yellow, orange or greyish-brown pigment occurring
with a special superstructure consisting of narrow ridges, as in some
parrots and pittas (ant-thrushes), or the surface of the barbs and
barbules is smooth and transparent, while between it and the pigment
there exists a layer of small polygonal, colourless bodies having highly
refractory, and often striated, surfaces.
Blue is unknown as a pigment in feathers. Blue feathers contain only
orange or brownish pigment (Gadow), the blue colour being caused by the
combination of pigment corpuscles and colourless striated polygonal
bodies, as in green feathers.
While in many birds the coloration takes the form either of a uniform
hue or of bands and patches of colour more or less brilliant, in others
the coloration is sombre, and made up of dark longitudinal stripes or
transverse bars on a lighter ground. The latter is the more primitive,
and there seems good reason to believe that longitudinal stripes
preceded transverse bars. This is indicated by the fact that the
nestlings of the more primitive groups are longitudinally striped, and
that young hawks in their first plumage are so striped, while the adults
are barred.
There is also evidence to show that the evolution of brilliant plumage
began with the males, and has, in many cases, been more or less
perfectly acquired by the females, and also by the young, as for example
in the kingfishers, where parents and offspring wear the same livery.
Often, where the parents are alike in plumage, the young wear a
different and duller livery, as in the case of the common starling
(_Sturnus vulgaris_). But where the female differs from the male in
coloration the young resemble the female parent.
The physiological explanation of complete disappearance of pigment in
adult life, e.g. gannet, is not yet apparent.
Moulting.
At least once annually birds renew their feathers completely by a
process known as a moult. Until the new feathers have attained at least
half their full length they are invested in a soft sheath, and, as
development proceeds, the sheath breaks up from the tip of the feather
downwards, so that for a time the new feathers have almost a brush-like
appearance. Generally this replacement takes place gradually, new and
old feathers occurring side by side, and on this account it is not
always possible to see whether a moult is proceeding without raising the
old feathers.
The "quill" feathers of the wing and tail are renewed in pairs, so that
flight is little, if at all, impaired, the change taking place in the
wing from the region of the wrist inwards, as to the primaries, and from
the body outwards, towards the tip of the wing, as to the secondaries.
In certain birds, however, as in the duck tribe and the rails, for
example, all the quill-feathers of the wing are shed at once, so that
for some time flight is impossible.
In the penguins this simultaneous method of moulting is carried still
further. That is to say, the old feathers covering the body are not
replaced gradually, but _en masse_. This method of ecdysis is, however,
still further remarkable in that the old feathers do not drop out, to be
succeeded by spine-like stumps which, later, split at the tip,
liberating the barbs of the new feathers. They are, on the contrary,
thrust out upon the tips of the new feathers, the barbs of which are
never enclosed within an envelope such as that just described. When
their growth has practically completed, and not till then, the old
feathers are removed in large patches by the aid of the bird's beak;
exposing thereby a perfectly developed plumage. In the cassowary, and
emeu, the old feathers similarly adhere for a time to the tips of the
new; but in these birds the feathers are moulted singly as in other
birds.
Some birds moult twice within the year, the additional moult taking
place in the spring, as in the case of the "warblers" (Sylviidae) and
Limicolae, for example. But when this is the case the spring moult is
only partial, since the quill feathers of the wings and the tail
feathers are not renewed.
At this spring moult a special "nuptial" plumage is often assumed, as
for example in many of the Limicolae, e.g. god-wits, knots, dunlin,
ruff.
The sequel to this habit of assuming a nuptial dress is an interesting
one. Briefly, this plumage, at first assumed at the mating period by the
males only, and doffed soon after the young appear, has become retained
for longer and longer periods, so that the succeeding plumage, often
conspicuously dull compared with the nuptial dress, is worn only for a
few weeks, instead of many months, as in the case of many of the ducks,
for example; wherein the males, as soon as the young are hatched, assume
what C. Waterton has aptly called an "eclipse" dress. This, instead of
being worn till the following spring, as in the waders, is shed again in
the autumn and replaced by what answers to the waders' "nuptial" dress.
In the game-birds but a trace of this "eclipse" plumage remains; and
this, apparently, only in jungle-fowl, the common grey partridge
(_Perdix cinerea_) and the blackcock (_Lyrurus_), in whose case the head
and neck for a short period following the breeding season are clothed
only by dull feathers. Further, this more highly developed plumage
becomes transferred, first to the female, then to the young, so that, in
many groups, the dull phase of plumage is entirely eliminated.
But the assumption at the breeding season of a conspicuously brilliant
plumage is not always due to a moult. In many birds, notably many
Passerines, this change is brought about by shedding the tips of the
feathers, which are of a duller hue than the rest of the feather. In
this way the bright rose pink of the linnet's breast, the blue and black
head of the chaffinch, and the black throat and chestnut-and-black
markings of the back of the sparrow, are assumed--to mention but a few
instances. These birds moult but once a year, in the autumn, when the
new feathers have broad brown fringes; as the spring advances these drop
off, and with them the barbicels from the barbules of the upper surface
of the feather, thus revealing the hidden tints.
According to some authorities, however, some birds acquire a change of
colour without a moult by the ascent of pigment from the base of the
feather. The black head assumed by many gulls in the spring is, for
example, said to be gained in this way. There is, however, not only no
good evidence in support of the contention, but the whole structure of
the feather is against the probability of any such change taking place.
The development of feathers.
Feathers correspond with the scales of reptiles rather than with the
hairs of mammals, as is shown by their development. They make their
first appearance in the developing chick at about the sixth day of
incubation, in the shape of small papillae. In section each papilla is
found to be made up of a cluster of dermal cells--that is to say, of
cells of the deeper layer of the skin--capped by cells of the
epidermis. These last form a single superficial layer of flattened
cells--the _epitrichium_--overlaying the cells of the Malpighian
layer, which are cylindrical in shape and rapidly increase to form
several layers. As development proceeds the papillae assume a
cone-shape with its apex directed backwards, while the base of this
cone sinks down into the skin, or rather is carried down by the growth
of the Malpighian cells, so that the cone is now sunk in a deep pit.
Thereby these Malpighian cells become divided into two portions: (1)
those taking part in the formation of the walls of the pit or "feather
follicle," and (2) those enclosed within the cone. These last surround
the central mass or core formed by the dermis. This mass constitutes
the nutritive pulp for the development of the growing feather, and is
highly vascular. The cells of the Malpighian layer within the cone now
become differentiated into three layers. (1) An inner, extremely thin,
forming a delicate sheath for the pulp, and found in the fully
developed feather in the form of a series of hollow, transparent caps
enclosed within the calamus; (2) a thick layer which forms the feather
itself; and (3) a thin layer which forms the investing sheath of the
feather. It is this sheath which gives the curious spine-covered
character to many nestling birds and birds in moult. As growth
proceeds the cells of this middle layer arrange themselves in
longitudinal rows to form the barbs, while the barbules are formed by
a secondary splitting. At their bases these rudimentary barbs meet to
form the calamus. Finally the tips of the barbs break through the
investing sheath and the fully formed down-feather emerges.
A part of the pulp and Malpighian cells remains over after the
complete growth of the down-feather, and from this succeeding
generations of feathers are developed. The process of this development
differs from that just outlined chiefly in this: that of the
longitudinal rows which in the down-feather form the barbs, two on the
dorsal and two on the ventral aspect of the interior of the cylinder
become stronger than the rest, combining to form the main-and
after-shaft respectively. The remainder of the rods form the barbs and
barbules as in the down-feather.
The reproductive power of the feather follicle appears to be almost
inexhaustible, since it is not diminished appreciably by age, nor
restricted to definite moulting periods, as is shown by the cruel and
now obsolete custom of plucking geese alive, no less than three times
annually, for the sake of their feathers. The growth of the feathers
is, however, certainly affected by the general health of the bird,
mal-nutrition causing the appearance of peculiar transverse V-shaped
grooves, at more or less regular intervals, along the whole length of
the feather. These are known as "hunger-marks," a name given by
falconers, to whom this defect was well known.
It would seem that while the feather germ may be artificially
stimulated to produce three successive generations of feathers within
a year, it may, on the other hand, be induced artificially to maintain
a continuous activity extending over long periods. That is to say, the
normal quiescent period, and periodic moult, may be suspended, so that
the feather maintains a steady and continuous growth till it attains a
length of several feet. The only known instance of this kind is that
furnished by a domesticated breed of jungle-fowl known as the
"Japanese long-tailed fowls" or as "Yokohamas." In this breed the
upper tail coverts are in some way, as yet unknown to Europeans,
induced to go on growing until they have attained a length of from 12
to 18 or even 20 ft.! In this abnormal growth the "hackles" of the
lower part of the back also share, though they do not attain a similar
length.
The feathers of birds are not uniformly distributed over the body, but
grow only along certain definite tracts known as _pterylae_, leaving
bare spaces or _apteria_. These pterylae differ considerably in their
conformation in different groups of birds, and hence are of service in
systematic ornithology.