his middle tube is perfectly air-tight. This union is secured by
a number of hairy projections which interlock, much as one's clasped
fingers interlock. Only the middle tube is used for the passage of the
honey, the side tubes being used, as some think, for breathing purposes,
while others hold that they serve to help in pumping up the fluids into
the mouth. By this interlocking contrivance the tube can easily be
opened and cleaned, should the passage become blocked by solid
particles.

Delicate as this wonderful 'tongue' appears to be, it is in some cases
capable of inflicting wounds on the tissues of the food plants. A
species of moth, for instance, causes considerable damage to crops of
oranges by inserting its trunk through the peel so as to suck the juices
of the enclosed pulp. The sucking action is performed by means of a
small bag inside the head, the size of which can be alternately
increased and decreased by the action of muscles, thus causing a pumping
action.

[Illustration: Fig. B.--Fly's Tongue (greatly magnified).]

It will probably surprise many readers of _Chatterbox_ to learn that
this wonderful tongue is by no means always found in butterflies, for
there are many species which have no mouth, and take no food whatever
after they emerge from the chrysalis stage. They simply live long enough
to lay their eggs, and then die!

[Illustration: Fig. C.--Common Fly.]

The tongue of the fly is every bit as wonderful as that of the
butterfly. Strictly speaking, perhaps it ought not to be called either a
tongue or a proboscis, for it is really a spout-like mouth bent upon
itself, and furnished at its end with a curious pair of flaps or lobes.
You may get an idea of what it is like if you imagine the spout of a
teapot to turn downwards at first instead of upwards, and then picture
the spout turned sharply forwards near its middle. The body of the
teapot corresponds to the fly's head; the end of the spout would
correspond to the mouth of the fly. On each side of this mouth there
will be found in the fly a pair of ear-shaped flaps or lobes, and these
play a very important part. Each flap or lobe (see fig. B), where it
joins the mouth, contains a long tube, and this tube gives off, along
its outer side, about thirty smaller tubes, which are open below. Now,
when the 'tongue,' as it is called, is extended, as in feeding, a
copious flow of saliva is sent down the long tubular mouth into the tube
of each flap, and