A bee's head
is dominated by two large compound
eyes. Between the compound eyes are three small ocelli or simple eyes which
register light levels. The vision of a bee is very different from human vision and what
bees actually may see can be viewed
here.
The antennae sit almost in the center of the face. Each is
composed of a basal stalk or scrape and a longer segmented flagellum. In drones, the
scrape is shorter but the flagellum has 12 segments. In workers and the queen, the
scrape is longer but the segmented flagellum only has 11 sections. The antennae are
controlled by four muscles and basically function as specialized sense organs. A large
proportion of the communication among bees in the the hive is done by antennae
touching.
The front of the mouth is composed of a wide plate or labrum. A proboscis is formed by
bringing together several lower mouth parts. The two maxillae and the median labium (
a movable flap) form the proboscis which is the tube used for feeding on nectar. When
the proboscis is not in use, it is folded up under the head.
A bee's tongue is covered by rings of cartilage bearing hairs and separated by smooth
membranous intervals. The tip of the tongue is a small spoon shaped lobe or flabellum
that is smooth on the underside, but covered with branched spines along the edges
and top. Muscles associated with the tongue allow the bee to "lap" at fluids. A sucking
pump also assists in feeding. The pump is a large muscled sac in the head. Dilator
muscles suck liquid up the proboscis in a way similar to the way a turkey baster bulb
works. Compressor muscles then close the mouth and food goes into the pharynx then
the esophagus. Since bees both ingest and egest food, the pump working in reverse
also serves in the feeding of developing larvae. Salivary glands to moisten food,
mandibular glands for the production of queen substance and brood food glands which
produce royal jelly are also located in the head. The brood food glands have a special
opening into the mouth area, and nurse bees discharge this nutritious food to
developing larvae through partially opened mandibles.
The thorax
is the middle portion of the bee's body
where the legs and wings are attached. Each pair of legs are specialized in structure
for performing different activities. The front legs are used to clean the head, eyes and
mouth and also have a special cleaning apparatus for grooming the antennae. The
middle pair of legs are used to clean the body, loosen pollen from the pollen baskets,
clean the wings and move wax plates that are secreted from glands on the abdomen.
The hind legs are specialized for pollen collection. Each leg is flattened, and on
workers are covered with long fringed hairs that form the pollen basket. Pollen grain
which adhere to the hairs of the body are brushed back to the inside of the hind leg
where they are stored in the pollen basket for carrying back to the hive. Propolis is
also carried back to the hive in the pollen baskets.
The two sets of wings are also attached to the thorax. The wings are membranous,
and strengthened by veins. Large flight muscles in the thorax power the wings in flight,
and at rest the wings are folded back along the body. The forewings which are longer,
are kept in unison with the beat of the hind wings by a Velcro style set of hooks that
keep the two wings connected.
The abdomen
contains the digestive, and reproductive
organs of the bee. There are several abdominal segments, each composed of an
upper tergum, and a lower sternum with the lower portion overlapping the segment
behind it. Some of the sterna are covered with wax producing glands, and during the
12th to 18th day of life, these are most developed and are used in the production of
wax scales used for comb building. As the bees age, the wax producing glands
degenerate and disappear. You might want to read more about the
Mathematics of Honeycomb .
On the upper abdomen at segment seven are the scent producing glands. The
Nasanoff gland produces a pheromone used at the entrance to the hive or in a swarm
to guide other workers to the proper location.
At the end of the abdomen is the sting, which when not in use is completely retracted
into the abdomen. The sting is made of an upper stylet and two lower lancets. The
stylet has a wide bulb at the upper end and connects with the poison sac. When the
bee stings, the entire apparatus works its way into the wound, continually discharging
venom. Since muscles associated with the poison sac continue to pump venom as the
stinger enters the wound, any delay in removing the sting can allow additional venom
into the victim.
An electron microscopist in Hawaii has the head of a bee
and a great image of the
stinger
on her website!
Another site with
anatomy details also contains a special STRIDULATORY FILE, a must
for everyone with Java enabled browsers! There is a separate section
on internal
anatomy.
An excellect insect
anatomy tutorial has been done, by Gordon Ramel over in the UK. This is
the place to learn about everything from the pedicel to the sting!
The mouth parts of a bee are complex. The mandibles (jaws) are suspended from the
head at the sides of the mouth. They are used in handling objects, manipulating pollen
and in contact with other bees. Above the mandibles is the mandibular gland which
secretes a substance once thought to be used to soften wax. It's now known that the
mandibular gland of the queen secretes QUEEN SUBSTANCE, the pheromone
responsible for maintenance of the social organization of the colony. The mandibular
glands are almost completely reduced in the drone.
Back to the Bee Biology page or 
Last modified 8 February 1999