=KINDS OF BEES COMPOSING A COLONY--BEE PRODUCTS AND
DESCRIPTION OF COMBS--DEVELOPMENT OF BROOD.=
KINDS OF BEES IN A COLONY.
Each colony of bees in good condition at the opening of the season
contains a laying queen and some 30,000 to 40,000 worker bees, or six
to eight quarts by measurement. Besides this there should be four,
five, or even more combs fairly stocked with developing brood, with a
good supply of honey about it. Drones may also be present, even several
hundred in number, although it is better to limit their production to
selected hives, which in the main it is not difficult to accomplish.
Under normal conditions the queen lays all of the eggs which are
deposited in the hive, being capable of depositing under favorable
conditions as many as 4,000 in twenty-four hours. Ordinarily she mates
but once, flying from the hive to meet the drone--the male bee--high
in the air, when five to nine days old generally, although this time
varies under different climatic conditions as well as with different
races. Seminal fluid sufficient to impregnate the greater number of
eggs she will deposit during the next two or three years (sometimes
even four or five years) is stored at the time of mating in a sac--the
spermatheca, opening into the oviduct or egg-passage (fig. 5, _s_).
The queen seems to be able to control this opening so as to fertilize
eggs or not as she wills at the time of depositing them. If fertilized
they develop into workers or queens according to the character of the
food given, the size and shape of the cell, etc.; if unfertilized,
into drones. The queen's life may extend over a period of four or five
years, but three years is quite as long as any queen ought to be kept,
unless a particularly valuable one for breeding purposes and not easy
to replace. Indeed, if full advantage be taken of her laying powers it
will rarely be found profitable to retain a queen longer than two years.
Upon the workers, which are undeveloped females, devolves all the labor
of gathering honey, pollen, propolis, and bringing water, secreting
wax, building combs, stopping up crevices in the hive, nursing the
brood, and defending the hives. To enable them to do all this they are
furnished with highly specialized organs. These will be more fully
referred to in connection with the description of the products gathered
and prepared by the workers.
[Illustration: Fig. 6.--A, Head of queen, magnified ten times, showing
smaller compound eyes at sides, and three ocelli on vertex of head;
_n_, jaw notch. B, head of drone, magnified ten times, showing larger
compound eyes at sides, with three ocelli between; _n_, jaw notch.
(From Cheshire.)]
The drones, aside from contributing somewhat to the general warmth
of the hive necessary to the development of the brood, seem to have
no other office but that connected with reproduction. In the wild
state colonies of bees are widely separated, being located wherever
the swarms chance to have found hollow trees or rock cavities, hence
the production of many drones has been provided for, so young queens
flying out to mate will not run too many risks from bird and insect
enemies, storms, etc. Mating in the hive would result in too continuous
in-and-in breeding, producing loss of vigor. As we find it arranged,
the most vigorous are the most likely to reproduce their species.
At the time of the queen's mating there are in the hive neither eggs
nor young larvæ from which to rear another queen; thus, should she be
lost, no more fertilized eggs would be deposited, and the old workers
gradually dying off without being replaced by young ones, the colony
would become extinct in the course of a few months at most, or meet a
speedier fate through intruders, such as wax-moth larvæ, robber bees,
wasps, etc., which its weakness would prevent its repelling longer; or
cold is very likely to finish such a decimated colony, especially as
the bees, because queenless, are uneasy and do not cluster compactly.
The loss of queens while flying out to mate is evidently one of the
provisions in nature to prevent bees from too great multiplication, for
were there no such checks they would soon become a pest in the land. On
the other hand, the risk to the queen is not uselessly increased, for
she mates but once during her life.
[Illustration: Fig. 7.--Modifications of the legs of different bees:
A, _Apis_: _a_, wax pincer and outer view of hind leg; _b_, inner
aspect of wax pincer and leg; _c_, compound hairs holding grains of
pollen; _d_, anterior leg, showing antenna cleaner; _e_, spur on tibia
of middle leg. B, _Melipona:_ _f_, peculiar group of spines at apex of
tibia of hind leg; _g_, inner aspect of wax pincer and first joint of
tarsus. C, _Bombus_: _h_, wax pincer; _i_, inner view of same and first
joint of tarsus--all enlarged. (From Insect Life.)]
BEE PRODUCTS AND ORGANS USED IN THEIR PREPARATION.
Pollen and honey form the food of honey bees and their developing
brood. Both of these are plant products which are only modified
somewhat by the manipulation to which they are subjected by the bees
and are then stored in waxen cells if not wanted for immediate use.
Pollen, the fertilizing dust of flowers, is carried home by the bees in
small pellets held in basket-like depressions on each of the hind legs.
The hairs covering the whole surface of the bee's body are more or less
serviceable in enabling the bee to collect pollen, but those on the
under side of the abdomen are most likely to get well dusted, and the
rows of hairs, nine in number, known as pollen brushes, located on the
inner surface of the first tarsal joint (fig. 7, _b_), are then brought
into use to brush out this pollen. When these brushes are filled with
pollen the hind legs are crossed during flight and the pollen combed
out by the spine-like hairs that fringe the posterior margin of the
tibial joint--that above a in fig. 7. The outer surface of this joint
is depressed, and this, with the rows of curved hairs on the anterior
margin and the straighter ones just referred to forms a basket like
cavity known as the corbiculum or pollen basket, represented by
the longest joints of the legs, A, B, and C, fig. 7. Into this the
pollen falls, and with the middle pair of legs is tamped down for
transportation to the hive. Having arrived there, the bee thrusts its
hind legs into a cell located as near to the brood nest as may be, and
loosening the pellets lets them fall into the bottom of the cell. The
tibial spur (fig. 7, _e_) on each middle leg is, as Professor Cheshire
has pointed out, probably of use in prying the pellets out. The latter
are simply dropped into cells and left for some other bee to pack down
by kneading or pressing with its mandibles. Various colors--yellow,
brown, red, slate, etc., according to the kinds of flowers from which
gathered--frequently show in layers in the same cell. Often when partly
filled with pollen the cell is then filled up with honey and sealed
more or less hermetically with wax. The bees store the pollen, for
convenience in feeding, above and at the sides of the brood and as
near to it as possible, the comb on each side of the brood nest being
generally well stored with it.
[Illustration: Fig. 8.--Head and tongue of Apis mellifera worker
(magnified twelve times), _a_, Antenna, or feeler; _m_, mandibula, or
outer jaw; _g_, gum flap, or epipharynx; _mxp_, maxillary palpus; _pg_,
paraglossa; _mx_, maxilla, or inner jaw; _lp_, labial palpus, _l_,
ligula, or tongue; _b_, bouton, or spoon of the same. (Reduced from
Cheshire.)]
NECTAR AND HONEY.
The liquid secreted in the nectaries of flowers is usually quite thin,
containing, when just gathered, a large per centage of water. Bees suck
or lap it up from such flowers as they can reach with their flexible,
sucking tongue, 0.25 to 0.28 inch long. (Fig. 8, _l_.) This nectar is
taken into the honey sac (Plate II, _h.s._) located in the abdomen, for
transportation to the hive. It is possible that part of the water is
eliminated by the gatherers before they reach the hive. A Russian bee
keeper, M. Nassanoff, while dissecting a worker, discovered between
the fifth and sixth abdominal segments a small canal, to which he
attributed an excretory function, and Zoubareff, having noticed bees
ejecting a watery substance while returning from the fields, suggested
that this gland probably served to separate a portion of the water from
the nectar, the liquid deposited in the cells appearing to contain less
of it than that just secreted by the flowers.
Bul. 1, new series, Div. of Entomology, U. S. Dept. of Agriculture.
Plate II.
[Illustration]
Digestive System of Bee (magnified ten times).
A, Horizontal section of body; _lp_, labial palpus; _mx_,, maxilla:
_e_, eye; _dv, dv_, dorsal vessel: _v_, ventricles of the same; No.
1. No. 2, No. 3, salivary gland systems, 1, 2, 3; _œ_, œsophagus;
_pro.t_, prothorax; _mesa.t_, mesathorax; _meta.t_, metathorax; _g,
g_, ganglia of chief nerve chain; _n_, nerves; _hs_, honey sac; _p_,
petaloid stopper of honey sac or stomach mouth; _c.s_, chyle stomach:
_bt_, biliary or Malpighian vessels: _si_, small intestine; _l_,
lamellæ or gland plates of colon; _li_, large intestine.
However this maybe, evaporation takes place rapidly in the heat of
the hive after the nectar or thin honey has been stored, as it is
temporarily, in open cells. Besides being thin, the nectar has at first
a raw, rank taste, generally the flavor and odor peculiar to the plant
from which gathered, and these are frequently far from agreeable. To
make from this raw product the healthful and delicious table luxury
which honey constitutes--"fit food for the gods"--is another of the
functions peculiar to the worker bee. The first step is the stationing
of workers in lines near the hive entrances. These, by incessant
buzzing of their wings, drive currents of air into and out of the hive
and over the comb surfaces. If the hand be held before the entrance
at such a time a strong current of warm air may be felt coming out.
The loud buzzing heard at night during the summer time is due to the
wings of workers engaged chiefly in ripening nectar. Instead of being
at rest, as many suppose, the busy workers are caring for the last
lot of gathered nectar and making room for further accessions. This
may go on far into the night, or even all night, to a greater or less
extent, the loudness and activity being proportionate to the amount and
thinness of the liquid. Frequently the ripening honey is removed from
one set of cells and placed in others. This may be to gain the use of
certain combs for the queen, or possibly it is merely incidental to
the manipulation the bees wish to give it. When, finally, the process
has been completed, it is found that the water content has usually
been reduced to 10 or 12 per cent, and that the disagreeable odors
and flavors, probably due to volatile oils, have also been driven off
in a great measure, if not wholly, by the heat of the hive, largely
generated by the bees. During the manipulation an antiseptic--formic
acid--secreted by glands in the head of the bee, and it is also
possible other glandular secretions, have been added. The finished
product is stored in waxen cells above and around the brood nest and
the main cluster of bees, as far from the entrance as it can be and
still be near to the brood and bees. The work of sealing with waxen
caps then goes forward rapidly, the covering being more or less porous.
Each kind of honey has its distinctive flavor and aroma, derived, as
already indicated, mainly from the particular blossoms by which it
was secreted, but modified and softened by the manipulation given it
in the hives. When the secretion is abundant in a flower having a
short or open corolla, hence one from which the bees find it easy to
obtain the honey, they will confine their visits to that kind if the
latter is present in sufficient numbers. Thus it is that linden, white
clover, buckwheat, white sage, mesquite, sourwood, aster, tulip tree,
mangrove, orange, and other kinds of honey may be harvested separately,
and each be readily recognizable by its color, flavor, consistency,
and aroma. When, however, no great honey yielder is present in large
quantity and the source is miscellaneous, all manner of combinations
of qualities may exist, introducing great and often agreeable variety.
Thus the medicinal qualities and the food value of different kinds of
honey differ as greatly as do their prices on the market.
PROPOLIS.
This substance, commonly known as "bee glue," is obtained by the bees
from the buds and crevices of trees, and is carried to the hives in
the corbicula or basket-like cavities on the outside of the tibial
joints of the workers' hind legs, the same as they carry pollen. The
workers with their mandibles scrape together and bite off the particles
of propolis, and with the front and middle legs pass them back to the
baskets, where the middle legs and feet are used to tamp them down. The
pellets can be readily distinguished from those of pollen, the latter
being dull and granular in appearance, while the freshly gathered
propolis is compact and shiny. This resinous material, which becomes
hard soon after it is gathered, is at first quite sticky, and the bee
bringing it requires aid in unloading. Another worker takes hold of
the mass with its jaws, and by united exertion they get it out of the
pocket, though often by piecemeal and in long threads. It is not stored
in cells, but is used at once to stop up crevices in the hives and to
varnish the whole interior surface, as well as to glue movable portions
fast, also in strengthening the combs at their attachments, and if the
latter are designed exclusively for honey, and especially if not filled
at once, the edges of their completed cells receive a thin coating of
propolis, which adds considerably to their strength. The bees often
make the flight hole smaller by filling a part of it with masses of
propolis, sometimes mixed with old wax. Carniolans gather the least
and Tunisians the most propolis of any of the different races. On this
account the former are better suited than the latter to the production
of fancy white comb honey.
BEE POISON AND THE STING.
The worker and the queen are supplied with another organ which is of
great importance to them, namely, the sting; for without this the
hard-earned stores of the hive would soon be a prey to all manner of
marauders, and the queen would be deprived of an organ of occasional
use to her in dispatching rivals, and of daily use to her during the
working season in the deposition of eggs. The darts work independently
and alternately, and are connected at the base with the poison sac,
without whose powerful contents such a tiny weapon would be wholly
ineffective. Poison glands pour an acid secretion--largely formic
acid--into this sac, whence it is conveyed to the tip of the sting
along the groove or canal formed by the junction of the sheath and the
darts. The sting being but an ovipositor modified also another purpose
in addition to oviposition, in the perfect female (the queen) its main
use is in placing the eggs in their proper position in the bottoms of
the cells.
Formic acid is known to have considerable antiseptic properties.
Chemical tests show its presence in well-ripened honey, but not in
freshly gathered nectar. The natural conclusion is that it has been
added by the bees to assist in the preservation of the honey. In what
manner it is supplied has frequently been questioned. Tests applied to
the blood of the bee show its presence there, and the secretions of the
head glands show still larger quantities. It is therefore reasonable
to suppose that these glands, as well as the poison glands themselves
secrete formic acid, and that the honey receives its portion from the
former, the head glands, upon being disgorged from the honey-sac or
during the manipulation to which it is subjected in the hive.
WATER.
During cold or cool weather much condensation of moisture takes place
in wooden hives as these are usually arranged. The water, collecting in
drops on the interior walls of the hive and on the cold, sealed honey,
often trickles down over the cluster of bees, to their great injury. It
has been claimed that when brood rearing begins this condensed moisture
will be utilized in the preparation of brood food. Very possibly it
may, yet its use is probably detrimental, since it is charged with
waste products of the hive--those of respiration, etc. In its absence
the water contained in the honey, if the latter has not granulated,
seems to be sufficient. Later, however, when no condensation takes
place in the hive and the greater number of developing larvæ require
considerable supplies of water in their food, special trips are made to
brooks and pools for it, and dew is often gathered from leaves.
SILK.
The larval bee produces a small amount of silk from glands in its
head. The pupal cell is partially lined with this. Later, as the bee
develops, there being no further use for the glands, they become
atrophied.
WAX.
The light colored pellets which are carried into the hive on the hind
legs of the workers, and which have been described as pollen, are often
mistaken for wax. The fact is, wax is not gathered in the form in which
we see it, except in rare instances, when, bits of comb having been
left about, small quantities will be loaded up and taken in as pellets
on the legs. Ordinarily it comes into the hive in the shape of honey
and is transformed by the workers within their own bodies into wax.
This production is wholly confined to the workers, for although the
queen has wax plates 011 the underside of the abdomen and wax glands
beneath them, yet both are less developed than in the workers and
are never used. The wax plates of the worker overlying the secreting
glands are well shown in fig. 9, those of the queen and of the related
genera, _Bombus_ and _Melipona_, being shown for comparison. During wax
secretion, that is, when combs are being built or honey cells sealed
over, a high temperature is maintained in the hive, and many workers
may be seen to have small scales of wax protruding from between the
segments of the abdomen on the underside. The molds or plates, eight
in number, in which the scales appear are concealed by the overlapping
of the abdominal segments, but when exposed to view (fig. 9, _a_) are
seen to be five-sided depressions lined with a transparent membrane.
The wax glands themselves are beneath this membrane, and through it the
wax comes in a liquid form. As the scales harden they are pushed out by
the addition of wax beneath. The bees pluck them out with neat pincers
(fig. 7, _a_ and _b_) formed by the articulation of the hind tibiæ
with the adjacent tarsal joints, pass them forward to the mandibles,
and mold them into the shape of hexagonal cells, meanwhile warming and
moistening them with the secretions of the head glands to render the
wax more pliable.
[Illustration: Fig. 9.--Wax disks of social bees: _a_, Apis mellifera
worker; _b_. A. mellifera queen; _c_, Melipona worker; _d_, Bombus
worker--all enlarged. (From Insect Life.)]
COMBS.
Wax is fashioned by the workers into cells of various sizes and shapes,
according to the use to be made of them. The most regular in shape and
size are the cells designed for brood (fig. 4). These combs in which
workers are bred show nearly 29 cells on a square inch of surface, the
combs being seven-eighths inch thick and the cells generally quite
regular hexagons in outline. Drone cells are larger, there being but
18 of them to the square inch of surface, and the comb is 1¼ inches
thick. The cells of combs designed only for honey are frequently more
irregular in shape, generally curve upward somewhat, and are often
deepened as the honey is stored in them, so that these combs sometimes
reach a thickness of 2 or 3 inches.
The cells in which queens are bred bear in size and shape some
resemblance to a ground or pea nut. They are often irregular in form,
being sometimes curved, or short and thick, according to the space
below their point of attachment, which is most frequently the lower
edge or the side edge of a comb, or sometimes a mere projection or
angularity in the general surface of a comb. Queen cells open downward
instead of being built horizontally like drone and worker cells (figs.
62 and 63).
[Illustration: Fig. 10.--Comb building--side of hive removed.
(Original.)]
Into the material used in constructing brood combs bees often
incorporate bits of wax and fiber-like gnawings of cocoons from
old combs in which brood has been reared, and if given cappings or
trimmings of combs they will work them all over and utilize most of
the material. Also when the bees have abundant supplies of pollen much
of this is incorporated into the material of brood combs, thus saving
the costlier substance--wax. Such combs show at once by their brownish
or straw color, even when first constructed, that they are not made of
wax alone. It will readily be seen from the above that the quantity
of honey consumed by the bees in producing a pound of comb must vary
greatly, for if the comb is designed for surplus honey it will be made
of newly secreted wax, while if for brood other material will, as
just stated, replace a portion of the wax. The amount of honey coming
in varies from day to day, and it is difficult to estimate how much
is consumed in feeding and keeping warm the brood: moreover, a high
temperature is required in the hive to facilitate the secretion and
working of wax, necessitating, of course, extra food consumption when
the outside temperature is low. Accordingly estimates as to the amount
of honey required to produce 1 pound of comb range from 5 pounds to 25
pounds. More accurate experiments are needed in this direction before
anything positive can be stated. Until then 18 to 20 pounds might be
looked upon as nearest the correct figure for white surplus combs, and
half as much for dull straw-colored or brownish combs built for brood
rearing.
DEVELOPMENT OF BROOD.
Ordinarily the winter cluster in a hive of bees occupies the more
central combs, four or five in number. Near the middle of this
cluster the queen deposits the first eggs of the season (which are
fertilized eggs) in the small-sized or worker cells. Under favorable
circumstances, that is, in a strong colony amply protected against
inclement weather, this deposition usually occurs in January, though
in a very mild climate some brood is generally present during every
month of the year, and the cessation of egg-laying is very short. The
eggs hatch on the third day after deposition into minute white larvæ,
to which the workers supply food in abundance. The composition of this
food has been the subject of much attention and more theorizing. It may
be considered as pretty certain that during the first three days of the
life of the larva its food is a secretion from glands located in the
heads of the adult workers--a sort of bee milk, to which, after the
third day, honey is added in the case of the worker larvæ, and honey
and pollen in the case of drone larva?. As this weaning proceeds both
worker and drone larvæ receive pollen, and in constantly increasing
proportions, in place of the secretion. But this rich albuminous
substance is continued to the queen larvæ throughout their whole period
of feeding; moreover, the quantity of this food supplied to each queen
larva is apparently super-abundant, for after it ceases to feed quite a
mass of the food somewhat dried out will be found in the bottom of the
cell from which a well-developed queen has issued. After assuming the
pupa form the young queen is attached to this food by means of the tip
of the abdomen, and it very likely continues for some time to receive
nourishment from the mass.
The following table shows approximately the time occupied in the
development of worker, drone, and queen:
+----------+---------+---------+---------+-----------------+
| | | | | From deposition |
| | Egg. | Larva. | Pupa. | of egg to imago.|
+----------+---------+---------+---------+-----------------+
| | _Days._ | _Days._ | _Days._ | _Days._ |
| Queen | 3 | 5½ | 7 | 15½ |
| Worker | 3 | 5 | 13 | 21 |
| Drone | 3 | 6 | 15 | 24 |
+----------+---------+---------+---------+-----------------+
The original circles of brood are gradually increased by the deposition
of eggs in the cells next outside those already occupied, and circles
are soon begun in the adjoining combs. In this way the space occupied
by the developing bees is gradually increased, while preserving the
general spherical shape of the brood nest thus formed, which, however,
the shape of the hive often modifies somewhat. As already mentioned,
each circle of brood has rows of pollen cells about it, chiefly above
and at the sides, and the combs on either side contiguous to the brood
are usually well packed with pollen. Outside of the pollen most of
the honey on hand is stored. Thus (fig. 11) a cross section made in
any direction through the middle of a hive in normal condition at the
opening of the active season should show this relative arrangement
of brood, pollen, and honey, which economizes most the heat of the
hive and the labors of the nurse bees, favoring in this way the rapid
increase of the population.
[Illustration: Fig. 11.--Cross section of brood apartment: _s, s_,
sides of hive; _t, t_, top-bars of frames; _h, p, l, sb_, combs
containing (_h_) honey, (_p_) pollen, (_l_) larvæ and eggs, and (_sb_)
sealed brood. (Original.)]
THE WORKER.
The worker larvæ are fed five days, and then the cell is given by the
adult bees a covering which is quite porous by reason of numerous
pollen grains incorporated into its mass, this openness of texture
being necessary to give the developing bee air to breathe. The larva
strength ens this capping by a loose webwork of silk within, extending
down the side but slightly and attached at its edges to the last skin
cast by the molting larva. This skin, extremely delicate and pressed
closely against the inside of the cell, forms the lining of its sides
and bottom. In about twelve days after sealing, that is, twenty-one
days from the time the egg was deposited, the imago, or perfect bee,
bites its way through the brown covering.
In the course of a couple of days it takes up the work of a nurse, and
in a week to ten days may appear at the entrance on pleasant days,
taking, however, but short flights for exercise, as ordinary field work
is not undertaken until it has passed about two weeks in the care of
brood. The worker then takes up also wax secretion, if honey is to be
capped over or combs built, although old bees can and do to a certain
extent engage in wax production.
THE DRONE.
Eggs left unfertilized produce drones and require twenty-four days
from the time they are deposited until the perfect insect appears.
They are normally deposited in the larger-sized horizontal cells, and
when the latter are sealed, the capping is more convex as well as
lighter-colored than that of worker brood, which is brown and nearly
flat.
The fact that drones develop from unfertilized eggs is to be noted
as having an important practical bearing in connection with the
introduction of new strains of a given race or of new races of bees
into an apiary. From a single choice home-bred or imported mother,
young queens of undoubted purity of blood may be reared for all of the
colonies of the apiary, and since the mating of these young queens
does not affect their drone progeny, thereafter only drones of the
desired strain or race and pure in blood will be produced, rendering,
therefore, the pure mating of future rearings fairly certain if other
bees are not numerous within a mile or two. Eventually also all of
the colonies will be changed to the new race and without admixture of
impure blood, provided always that the young queens be reared from
mothers of pure blood mated to drones of equal purity.