[Illustration: FIG. 24 (Spalteholz). Shows the arytenoid cartilages, the most important of all the cartilages of the larynx, inasmuch as to the part termed "vocal process" the vocal band is attached on each side. The movements of the vocal bands are nearly all determined by the movements of these cartilages, which have a swivel-like action. In the above the front surfaces are turned toward each other.] The _cricoid_ (_krikos_, a signet-ring) is the cartilage next in size. It is situated below the thyroid cartilage, with which it is connected by a membrane, the crico-thyroid. The wider part of this signet-ring is situated behind, where it affords attachment to large muscles. It also furnishes a base of support for two very important structures, the _arytenoid_ (_arutaina_, a ladle) cartilages. As the vocal bands are attached behind to them, and as they have a large degree of mobility, they are from a physiological point of view the most important of all the solid structures of the larynx. There are two pairs of small bodies, the _cartilages of Santorini_, or _cornicula laryngis_, surmounting the arytenoids, and the _cuneiform_, or _cartilages of Wrisberg_, situated in the folds of mucous membrane on each side of the arytenoids; but these structures are of little importance. The whole of the inner surface of the larynx is lined with mucous membrane, though that covering over the true vocal bands is very thin, and so does not cause them to appear red like the false vocal bands, which are merely folds of the mucous membrane. However, the true vocal bands may become red and thickened when inflamed, because of this same mucous membrane, which, though ordinarily not visible to the eye, becomes so when the condition referred to is present; for inflammation is always attended by excess in the blood supply, with a prominence of the small blood-vessels resulting in a corresponding redness. The same thing happens, in fact, as in inflammation of the eyes or the nose, both of which are more open to observation. Bearing this in mind one can readily understand why in such a condition, which is often approached if not actually present in the case of "a cold," the voice becomes so changed. Such vocal bands are clumsy in movement, as the arms or any other part would be if thus swollen. The plain remedy is rest, cessation of function--no speaking, much less attempts at singing. Like the nose the larynx, and especially the vocal bands, may be catarrhal, and such a condition may call for medical treatment before the speaker or singer can do the most effective vocal work.