10 .-- THE LUNGS AND WINDPIPE.

Parts of the lungs have been removed to show the branching of the air tubes or bronchi which pass into them.

All the tubes and the surfaces of the lungs communicate with the inner surface of the body through the larynx.] The nervous system (Fig.

8) represents one of the most important of the enclosed organs.

It serves an important function, not only in regulating and cooerdinating all functions, but by means of the special senses which are a part of it, the relations of the organism as a whole with the environment are adjusted.