THE LEGS
The legs of the bee are not only used for walking but they have also to
take the place of hands and arms. They are divided into three pairs,
one attached to each division of the thorax. Each leg has nine joints,
which have separate names. The last joint, which is really the foot,
has two claws and a kind of soft pad. The claws, a picture of which is
shown in (_b_) Plate IX., are useful for walking over rough surfaces,
and also serve as little hooks. When the bees are wax-making they hook
their feet together, just as we take hold of hands, and they are thus
able to hang in long festoons from the roof of the hive.
The pad is called the “pulvillus,” and is close to the claws. We all
know how easily a fly can walk upside down on the ceiling, or run up
a window pane. It is able to do this by means of pads which it also
possesses. These pads are covered with a kind of gummy liquid, and
by their aid a fly or a bee can walk up, or perhaps it would be more
correct to say stick to, a window pane or other smooth surface. The
fly, however, can beat the bee when walking on such surfaces, because
it has two pads on each foot, whereas the bee has only one. On the
other hand, the claws of the fly have no hooks, therefore flies cannot
cling to each other as bees do.
It is very interesting to understand how the pads are brought into use
by the bee. You must remember that they are placed just above the claw
itself; when the bee is walking over an uneven surface the claw catches
on the roughnesses, and then the pad remains in its ordinary position.
When the bee comes to a slippery surface, however, the claw is not able
to obtain a grip, and so it slips down under the foot, its place being
taken by the pad. This presses against the smooth surface and adheres
to it by means of the sticky moisture with which it is covered. Here is
a sketch showing the pad just coming into action.
[Illustration]
The pads hold very tightly on to a smooth surface when they are pulled
_downwards_, as it were, by the weight of the bee. But they are very
easily loosened if the sides are lifted up, and in this manner they may
be peeled off the smooth surface, just as we take a stamp off a letter.
So beautiful is this arrangement, and so perfect in its action, that it
is stated a bee can put down and lift up each foot at least 1200 times
a minute!