Fertile Workers
It has already been remarked, that the workers are proved by dissection
to be females, all of which, under ordinary circumstances, are barren.
Occasionally, some of them appear to be more fully developed than
common, so as to be capable of laying eggs: these eggs, like those of
Queens whose impregnation has been retarded, _always produce drones_!
Sometimes, when a colony has lost its Queen, these drone-laying workers
a
e exalted to her place, and treated with equal respect and affection,
by the bees. Huber ascertained that these fertile workers were generally
reared in the neighborhood of the young Queens, and he thought that they
received some particles of the peculiar food or jelly on which the
Queens are reared. (See Royal Jelly.) He did not pretend to account for
the effect of retarded impregnation; and made no experiments to
determine the facts, as to the fecundation of these fertile workers.
Since the publication of Huber's work, nearly 50 years ago, no light has
been shed upon the mysteries of drone-laying Queens and workers, until
quite recently. Dzierzon appears to have been the first to ascertain the
truth on this subject; and his discovery must certainly be ranked as
unfolding one of the most astonishing facts in all the range of
animated nature. This fact seems, at first view, so absolutely
incredible, that I should not dare to mention it, if it were not
supported by the most indubitable evidence, and if I had not, (as I have
already observed,) determined to state all important and well
ascertained facts, without seeking, by any concealments, to pander to
the prejudices of conceited, and often, very ignorant Bee-Keepers.
Dzierzon advances the opinion that impregnation is not needed in order
that the eggs of the Queen may produce drones; but, that all impregnated
eggs produce females, either workers or Queens; and all unimpregnated
ones, males or drones! He states that he found drone-laying Queens in
several of his hives, whose wings were so imperfect that they could not
fly, and that on examination, they proved to be unfecundated. Hence he
concluded that the eggs of the Queen Bee or fertile worker, had from the
previous impregnation of the egg which produced them, sufficient
vitality to produce the drone, which is a less highly organized insect,
and one inferior to the Queen or workers. It had long been known, that
the Queen deposits drone eggs in the large or drone cells, and worker
eggs in the small or worker cells, and that she makes no mistakes.
Dzierzon inferred, therefore, that there was some way in which she was
able to decide as to the sex of the egg before it was laid, and that she
must have a control over the mouth of the seminal sac, so as to be able
to extrude her eggs, allowing them to receive or not, just as she
pleased, a portion of its fertilizing contents. In this way he thought
she determined the sex, according to the size of the cells in which she
laid them. Mr. Samuel Wagner of York, Pa., has recently communicated to
me a very original and exceedingly ingenious theory of his own, which he
thinks will account for all the facts without admitting that the Queen
Bee has any special knowledge or will on the subject. He supposes that
when she deposits her eggs in the worker cells, her body is slightly
compressed by the size of the cells, and that the eggs, as they pass the
spermatheca, receive in this manner, its vivifying influence. On the
contrary, when she is egg-laying in drone cells, this compression cannot
take place, the mouth of the spermatheca is kept closed, and the eggs
are, necessarily, unfecundated. This theory may prove to be true, but at
present, it is encumbered with some difficulties and requires further
investigation, before it can be considered as fully established.
Leaving then the question whether the Queen exercises any volition in
this matter, for the present undecided, I shall state some facts which
occurred in the summer of 1852, in my own Apiary, and shall then
endeavor to relieve, as far as possible, this intricate subject from
some of the difficulties which embarrass it.
In the Autumn of 1852, my assistant found, in one of my hives, a young
Queen, the whole of whose progeny was drones. The colony had been formed
by removing part of the combs containing bees, brood and eggs from
another hive. It had only a few combs, and but a small number of bees.
They raised a new Queen in the manner which will hereafter be
particularly described. This Queen had laid a number of eggs in one of
the combs, and the young bees from some of them were already emerging
from the cells. I perceived, at the first glance, that they were drones.
As there were none but worker cells in the hive, they were reared in
them, and not having space for full development, they were dwarfed in
size, although the bees, in order to give them more room, had pieced out
the cells so as to make them larger than usual! Size excepted, they
appeared as perfect as any other drones.
I was not only struck with the singularity of finding drones reared in
worker cells, but with the equally singular fact that a young Queen, who
at first lays only the eggs of workers, should be laying drone eggs at
all; and at once conjectured that this was a case of a drone-laying,
unimpregnated Queen, as sufficient time had not elapsed for her
impregnation to be unnaturally retarded. I saw the great importance of
taking all necessary precautions to determine this point. The Queen was
removed from the hive, and carefully examined. Her wings, although they
appeared to be perfect, were so paralized that she could not fly. It
seemed probable, therefore, that she had never been able to leave the
hive for impregnation.
To settle the question beyond the possibility of doubt, I submitted this
Queen to Dr. Joseph Leidy for microscopic examination. The following is
an extract from his report: "The ovaries were filled with eggs; the
poison sac was full of fluid, and I took the whole of it into my mouth;
the poison produced a strong metallic taste, lasting for a considerable
time, and at first, it was pungent to the tip of the tongue. The
spermatheca was distended with a perfectly colorless, transparent,
viscid liquid, _without a trace of spermatozoa_."
This examination seems perfectly to sustain the theory of Dzierzon, and
to demonstrate that Queens do not need to be impregnated, in order to
lay the eggs of males.
I must confess that very considerable doubts rested on my mind, as to
the accuracy of Dzierzon's statements on this subject, and chiefly
because of his having hazarded the unfortunate conjecture that the place
of the poison bag in the worker, is occupied in the Queen, by the
spermatheca. Now this is so completely contrary to fact, that it was a
very natural inference that this acute and thoroughly honest observer,
made no microscopic dissections of the insects which he examined. I
consider myself peculiarly fortunate in having enjoyed the benefit of
the labors of a Naturalist, so celebrated as Dr. Leidy, for microscopic
dissections. The exceeding minuteness of some of the insects which he
has completely figured and described, almost passes belief.
On examining this same colony a few days later, I obtained the most
satisfactory evidence that these drone eggs were laid by the Queen which
had been removed. No fresh eggs had been deposited in the cells, and the
bees, on missing her, had commenced the construction of royal cells, to
rear if possible, another Queen, a thing which they would not have done,
if a fertile worker had been present, by which the drone eggs had been
laid.
Another very interesting fact proves that _all_ the eggs laid by this
Queen, were drone eggs. Two of the royal cells were, in a short time,
discontinued, and were found to be empty, while a third contained a
worm, which was sealed over the usual way, to undergo its changes from a
worm to a perfect Queen.
I was completely at a loss to account for this, as the bees having an
unimpregnated drone-laying Queen, ought not to have had a single female
egg from which they could rear a Queen.
At first I imagined that they might have _stolen_ it from another hive,
but when I opened this cell, it contained, instead of a queen, _a dead
drone_!
I then remembered that Huber has described the same mistake on the part
of some of his bees. At the base of this cell, was an extraordinary
quantity of the peculiar jelly or paste, which is fed to the young that
are to be transformed into queens. The poor bees in their desperation,
appear to have dosed the unfortunate drone to death: as though they
expected by such liberal feeding, to produce some hopeful change in his
sexual organization!
It appears to me that these facts constitute all the links in a perfect
chain, and demonstrate beyond the possibility of doubt, that
unfecundated queens are not only capable of laying eggs, (this would be
no more remarkable than the same occurrence in a hen,) but that these
eggs are possessed of sufficient vitality to produce drones. Aristotle,
who flourished before the Christian era, had noticed that there was no
difference in appearance, between the eggs producing drones and those
producing workers; and he states that drones only are produced in hives
which have no queen; of course the eggs producing them, were laid by
fertile workers. Having now the aid of powerful microscopes, we are
still unable to detect the slightest difference in size or appearance in
the eggs, and this is precisely what we should expect if the same egg
will produce either a worker or a drone, according as it is or is not
impregnated. The theory which I propose, will, I think, perfectly
harmonize with all the observed facts on this subject.
I believe that after fecundation has been delayed for about three weeks,
the mouth of the spermatheca becomes permanently closed, so that
impregnation can no longer be effected; just as the parts of a flower,
after a certain time, wither and shut up, and the plant is incapable of
fructification. The fertile drone-laying workers, are in my opinion,
physically incapable of being impregnated. However strange it may
appear, or even improbable, that an unimpregnated egg can give birth to
a living being, or that the sex can be dependent on impregnation, we are
not at liberty to reject facts, because we cannot comprehend the reasons
of them. He who allows himself to be guilty of such folly, if he seeks
to maintain his consistency, will be plunged, sooner or later, into the
dreary gulf of atheism. Common sense, philosophy and religion alike
teach us to receive all undoubted facts in the natural and the
spiritual world, with becoming reverence; assured that however
mysterious to us, they are all most beautifully harmonious and
consistent in the sight of Him whose "understanding is infinite."
There is something analogous to these wonders in the bee, in what takes
place in the aphides or green lice which infest our rose bushes and
other plants. We have the most undoubted evidence that a fecundated
female gives birth to other females, and they in turn to others still,
all of which, without impregnation, are able to bring forth young, until
at length, after a number of generations, perfect males and females are
produced, and the series starts anew!
The unequaled facilities, furnished by my hives, have seemed to render
it peculiarly incumbent on me, to do all in my power to clear up the
difficulties in this intricate and yet highly important branch of
Apiarian knowledge. All the leading facts in the breeding of bees ought
to be as well known to the bee keeper, as the same class of facts in the
rearing of his domestic animals. A few crude and hasty notions, but half
understood and half digested, will answer only for the old fashioned bee
keeper, who deals in the brimstone matches. He who expects to conduct
bee keeping on a safe and profitable system, must learn that on this, as
on all other subjects, "knowledge is power."
The extraordinary fertility of the queen bee has already been noticed.
The process of laying has been well described by the Rev. W. Dunbar, a
Scotch Apiarian.
"When the queen is about to lay, she puts her head into a cell, and
remains in that position for a second or two, to ascertain its fitness
for the deposit which she is about to make. She then withdraws her
head, and curving her body downwards,[2] inserts the lower part of it
into the cell: in a few seconds she turns half round upon herself and
withdraws, leaving an egg behind her. When she lays a considerable
number, she does it equally on each side of the comb, those on the one
side being as exactly opposite to those on the other as the relative
position of the cells will admit. The effect of this is to produce the
utmost possible concentration and economy of heat for developing the
various changes of the brood!"
Here as at every step in the economy of the bee our minds are filled
with admiration as we witness the perfect adaptation of means to ends.
Who can blame the warmest enthusiasm of the Apiarian in view of a
sagacity which seems scarcely inferior to that of man.
"The eggs of bees," I quote from the admirable treatise of Bevan, "are
of a lengthened oval shape, with a slight curvature, and of a bluish
white color: being besmeared at the time of laying, with a glutinous
substance,[3] they adhere to the bases of the cells, and remain
unchanged in figure or situation for three or four days; they are then
hatched, the bottom of each cell presenting to view a small white worm.
On its growing so as to touch the opposite angle of the cell, it coils
itself up, to use the language of Swammerdam, like a dog when going to
sleep; and floats in a whitish transparent fluid, which is deposited in
the cells by the nursing-bees, and by which it is probably nourished; it
becomes gradually enlarged in its dimensions, till the two extremities
touch one another and form a ring. In this state it is called a larva or
worm. So nicely do the bees calculate the quantity of food which will be
required, that none remains in the cell when it is transformed to a
nymph. It is the opinion of many eminent naturalists that farina does
not constitute the sole food of the larva, but that it consists of a
mixture of farina, honey and water, partly digested in the stomachs of
the nursing-bees."
"The larva having derived its support, in the manner above described,
for four, five or six days, according to the season," (the development
being retarded in cool weather, and badly protected hives,) "continues
to increase during that period, till it occupies the whole breadth and
nearly the length of the cell. The nursing bees now seal over the cell,
with a light _brown cover_, externally more or less _convex_, (the cap
of a drone cell is more convex than that of a worker,) and thus
differing from that of a honey cell which is _paler_ and somewhat
_concave_." The cap of the brood cell appears to be made of a mixture of
bee-bread and wax; it is not air tight as it would be if made of wax
alone; but when examined with a microscope it appears to be reticulated,
or full of fine holes through which the enclosed insect can have air for
all necessary purposes. From its texture and shape it is easily thrust
off by the bee when mature, whereas, if it consisted wholly of wax, the
young bee would either perish for lack of air, or be unable to force its
way into the world! Both the material and shape of the lids which seal
up the honey cells are different, because an entirely different object
was aimed at; they are of pure wax to make them air tight and thus to
prevent the honey from souring or candying in the cells! They are
concave or hollowed inwards to give them greater strength to resist the
pressure of their contents!
To return to Bevan. "The larva is no sooner perfectly inclosed than it
begins to line the cell by spinning round itself, after the manner of
the silk worm, a whitish silky film or cocoon, by which it is encased,
as it were, in a pod. When it has undergone this change, it has usually
borne the name of _nymph_ or _pupa_. The insect has now attained its
full growth, and the large amount of nutriment which it has taken serves
as a store for developing the perfect insect."
"The _working bee nymph_ spins its cocoon in thirty-six hours. After
passing about three days in this state of preparation for a new
existence, it gradually undergoes so great a change as not to wear a
vestige of its previous form, but becomes armed with a firmer mail, and
with scales of a dark brown hue. On its belly six rings become
distinguishable, which by slipping one over another enables the bee to
shorten its body whenever it has occasion to do so.
"When it has reached the twenty-first day of its existence, counting
from the moment the egg is laid, it comes forth a perfect winged insect.
The cocoon is left behind, and forms a closely attached and exact lining
to the cell in which it was spun; by this means the breeding cells
become smaller and their partitions stronger, the oftener they change
their tenants; and may become so much diminished in size as not to admit
of the perfect development of full sized bees."
"Such are the respective stages of the working bee: those of the royal
bee are as follows: she passes three days in the egg and is five a worm;
the workers then close her cell, and she immediately begins spinning her
cocoon, which occupies her twenty four hours. On the tenth and eleventh
days and a part of the twelfth, as if exhausted by her labor, she
remains in complete repose. Then she passes four days and a part of the
fifth as a nymph. It is on the sixteenth day therefore that the perfect
state of queen is attained."
"The drone passes three days in the egg, six and a half as a worm, and
changes into a perfect insect on the twenty-fourth or twenty-fifth day
after the egg is laid."
"The _development_ of _each species_ likewise proceeds more slowly when
the colonies are weak or the air cool, and when the weather is very cold
it is entirely suspended. Dr. Hunter has observed that the eggs, worms
and nymphs all require a heat above 70 deg. of Fahrenheit for their
evolution."
In the chapter on protection against extremes of _heat_ and _cold_, I
have dwelt, at some length, upon the importance of constructing the
hives in such a manner as to enable the bees to preserve, as far as
possible, a uniform temperature in their tenement. In thin hives exposed
to the sun, the heat is sometimes so great as to destroy the eggs and
the larvae, even when the combs escape from being melted; and the cold is
often so severe as to check the development of the brood, and sometimes
to kill it outright.
In such hives, when the temperature out of doors falls suddenly and
severely, the bees at once feel the unfavorable change; they are obliged
in self defence to huddle together to keep warm, and thus large portions
of the brood comb are often abandoned, and the brood either destroyed at
once by the cold, or so enfeebled that they never recover from the
shock. Let every bee keeper, in all his operations, remember that brood
comb must never be exposed to a low temperature so as to become chilled:
the disastrous effects are almost as certain, as when the eggs of a
setting hen are left, for too long a time, by the careless mother. The
brood combs are never safe when taken for any considerable time from the
bees, unless the temperature is fully up to summer heat.
"[4]The young bees break their envelope with their teeth, and assisted,
as soon as they come forth, by the older ones, proceed to cleanse
themselves from the moisture and exuviae with which they were surrounded.
Both drones and workers on emerging from the cell are, at first grey,
soft and comparatively helpless so that some time elapses before they
take wing.
"With respect to the cocoons spun by the different larvae, both workers
and drones spin _complete cocoons_, or inclose themselves on every side;
royal larvae construct only _imperfect cocoons_, open behind, and
enveloping only the head, thorax, and first ring of the abdomen; and
Huber concludes, without any hesitation, that the final cause of their
forming only incomplete cocoons is, that they may thus be exposed to the
mortal sting of the first hatched queen, whose instinct leads her
instantly to seek the destruction of those who would soon become her
rivals.
"If the royal larvae spun complete cocoons, the stings of the queens
seeking to destroy their rivals might be so entangled in their meshes
that they could not be disengaged. 'Such,' says Huber, 'is the
instinctive enmity of young queens to each other, that I have seen one
of them, immediately on its emergence from the cell, rush to those of
its sisters, and tear to pieces even the imperfect larvae. Hitherto
philosophers have claimed our admiration of nature for her care in
preserving and multiplying the species. But from these facts we must now
admire her precautions in exposing certain individuals to a mortal
hazard.'"
The cocoon of the royal larva is very much stronger and coarser than
that spun by the drone or worker, its texture considerably resembling
that of the silk worm's. The young queen does not come forth from her
cell until she is quite mature; and as its great size gives her abundant
room to exercise her wings she is capable of flying as soon as she quits
it. While still in her cell she makes the fluttering and piping noises
with which every observant bee keeper is so well acquainted.
Some Apiarians have supposed that the queen bee has the power to
regulate the development of eggs in her ovaries, so that few or many are
produced, according to the necessities of the colony. This is evidently
a mistake. Her eggs, like those of the domestic hen, are formed without
any volition of her own, and when fully developed, must be extruded. If
the weather is unfavorable, or if the colony is too feeble to maintain
sufficient heat, a smaller number of eggs are developed in her ovaries,
just as unfavorable circumstances diminish the number of eggs laid by
the hen; if the weather is very cold, egg-laying usually ceases
altogether. In the latitude of Philadelphia, I opened one of my hives on
the 5th day of February, and found an abundance of eggs and brood,
although the winter had been an unusually cold one, and the temperature
of the preceding month very low. The fall of 1852 was a warm one, and
eggs and brood were found in a hive which I examined on the 21st of
October. Powerful stocks in well protected hives contain some brood, at
least ten months in the year; in warm countries, bees probably breed,
every month in the year.
It is highly interesting to see in what way the supernumerary eggs of
the queen are disposed of. When the number of workers is too small to
take charge of all her eggs, or when there is a deficiency of bee bread
to nourish the young, (See chapter on Pollen,) or when, for any reason,
she judges it not best to deposit them in cells, she stands upon a comb,
and simply extrudes them from her oviduct, and the workers devour them
as fast as they are laid! This I have repeatedly witnessed in my
observing hives, and admired the sagacity of the queen in economizing
her necessary work after this fashion, instead of laboriously depositing
the eggs in cells where they are not wanted. What a difference between
her wise management and the stupidity of a hen obstinately persisting to
set upon addled eggs, or pieces of chalk, and often upon nothing at all.
The workers eat up also all the eggs which are dropped, or deposited out
of place by the queen; in this way, nothing goes to waste, and even a
tiny egg is turned to some account. Was there ever a better comment upon
the maxim? "Take care of the pence, and the pounds will take care of
themselves."
Do the workers who appear to be so fond of a tit-bit in the shape of a
new laid egg, ever experience a struggle between their appetites and the
claims of duty, and does it cost them some self denial to refrain from
making a breakfast on a fresh laid egg? It is really very difficult for
one who has carefully watched the habits of bees, to speak of his little
favorites in any other way than as though they possessed an intelligence
almost, if not quite, akin to reason.
It is well known to every breeder of poultry, that the fertility of a
hen decreases with age, until at length, she becomes entirely barren; it
is equally certain that the fertility of the queen bee ordinarily
diminishes after she has entered upon her third year. She sometimes
ceases to lay Worker eggs, a considerable time before she dies of old
age; the contents of the spermatheca are exhausted; the eggs can no
longer be impregnated and must therefore produce drones.
The queen bee usually dies of old age, some time in her fourth year,
although instances are on record of some having survived a year longer.
It is highly important to the bee keeper who would receive the largest
returns from his bees, to be able, as in my hives, to catch the queen
and remove her, when she has passed the period of her greatest
fertility. In the sequel, full directions will be given, as to the
proper time and mode of effecting it.
Before proceeding farther in the natural history of the queen bee, I
shall describe more particularly, the other inmates of the hive.