intestines and other abdominal organs which make movements. They are found also in the walls of the small blood vessels where their contractions or relaxations can change the caliber of the vessels, and so affect the amount of blood passing through them. A good example of this action is seen in the color of the face; when one is pale, it is because the small blood vessels just under the skin of the face are much contracted, and very little blood can pass through; when flushed, on the other hand, the blood vessels are relaxed and there is a large amount of blood passing. These contractions and relaxations of the blood vessels are performed by movements of the smooth muscles. Another interesting place where there are smooth muscles is at the roots of the hairs. Everybody knows that the hair is supposed to stand on end when one is frightened. Most of us have thought of this as a picturesque figure of speech, but as a matter of fact it actually does happen. A human being has such a small equipment of hair that its rising on end does not make much of a showing, but in an angry dog or frightened cat we see it in all its glory. If one looks at the forearm when it is so chilly that “goose-fleshing” occurs, he sees his hair then standing clearly on end. In fact, goose-fleshing is caused by contractions of these smooth muscles just under the skin. Every hair has a few smooth muscle cells at its base and they are attached in such a way that, when they contract, the hair is pulled from the slanting to the erect position. The surface of the skin acts as the fulcrum on which the motion is made. Besides these places where smooth muscle is found there are some in the eye. The muscles of accommodation and also those by which the size of the pupil is changed are smooth muscles. There are some also in the small bronchial passages. In persons who suffer from asthma these smooth muscles become contracted, and the difficulty in breathing experienced is the result of the partial closing of the air passages caused by this contraction. Glands which are under the control of the same kind of nerves as control the smooth muscles are found in many places in the body; in the head we have the tear glands and the salivary glands; in the trunk there are the gastric glands, the pancreatic, and various others about which we shall hear later. With the single exception of the muscles of accommodation there is no case either among the smooth muscles or the glands where there is any occasion for a finely subdivided control. When the muscles of the stomach or intestines become active, a great many fibers work together. When the hair stands on end, a great many hairs become affected at once. A flushing or paling of the skin is also a matter of a large surface. The same is true of gland secretion. In an active gland there is no picking out of a few cells to do the secretion, but a large part of the gland, if not the whole of it, becomes active, whenever any of it is.