SYMPTOMS.--The symptoms of this form of paralysis are for the most part such as depend upon the mechanical relation of the parts. There is no pain; there is no dyspnoea, except in cases in which there is a catarrh of the larynx; there is no cough. There is however, complete aphonia. There may be an exception to this statement when the paralysis is unilateral. It is possible that where one cord comes to the median line, and the other is affected only with paresis, in the course of time the cord on the sound side may pass beyond the median line and render phonation possible. In such cases, however, the voice is not normal in quality. Upon inspection with the laryngoscope the glottis is seen to be widely open. The cords approximate the lateral walls of the supraglottic space. Upon an effort to phonate the cords remain immobile. If the constrictors are unaffected, the act of laughing is still possible, from the fact that a partial occlusion of the lumen of the tube is accomplished by the action of the borders of the laryngeal opening and by the approximation of the false cords. In case of unilateral paralysis of course there is motion of the cord upon the sound side, leaving one-half of the glottis open. It has been stated by Von Ziemssen that there is sometimes an anæmic condition of the mucous surfaces. When present, this is probably only a contingent phenomenon, the evidence of a slight alteration of the circulation in the tissues. It is true that the permanent immobility of the parts ought to diminish the activity of the circulation in the muscles, and perhaps also in the neighboring structures. On the other hand, the surfaces have been found hyperæmic. Probably no importance should be attached to the surface condition as a means of diagnosis. {83} The course, duration, and termination of this form of paralysis must depend largely upon the cause. When the disorder depends upon a catarrh, we may expect that the trouble will disappear, or at least be mitigated, as the local affection is relieved. If of syphilitic or rheumatic origin, it should disappear pari passu with the primary disease. So far as we know, there is no danger to life, the loss of voice being the only important result. The DIAGNOSIS is easy. The laryngoscope will enable the observer to differentiate it from all other affections by which the voice is destroyed. It is possible that disease affecting the articulation of the arytenoids, and thus preventing their movement, might give rise to a doubt. A careful examination in such cases will, however, generally reveal the fact of tumefaction or other evidence of structural change. Closely allied to the paralyses which we have just been considering are the affections of the glottis of hysterical origin.