PROGNOSIS.--It is not favorable even in the simple and uncomplicated cases. Infants and children under two years almost invariably die. The percentage of average mortality rates very high--from 80 to 90 and more. It is probable that some recent therapeutical advances have reduced it, will reduce it, considerably. Tracheotomy is known to do so certainly, as from 20 to 45 out of 100 operations prove successful. The previous condition of the patient is of very little account in regard to the course and termination of the disease; no constitution protects or saves. The more the disease is local the better the prognosis. When fever makes its appearance, it means a complication, such as extending diphtheria or bronchitis or bronchi-pneumonia, and impairs the chances of recovery. The expectoration of membranous shreds or whole membranes does not improve the prognosis much, as the new formation of membranes may be very rapid indeed. I have seen new membranes rising to a formidable extent in from two to seven hours. The prognosis is improved when the cough becomes looser, expectoration more purulent, pulmonary respiration become audible again after having been covered by the laryngeal noises, rhonchi become moist, and portions of lungs which before were inaccessible to air by clogging membranes are reopened. Increasing debility, frequent and irregular pulse, are ominous symptoms. Even more so is the failure on the part of emetics to take effect. DIAGNOSIS.--It may be quite difficult to diagnosticate croupous from catarrhal laryngitis, particularly in those cases where the former is not complicated with any visible exudative process in the fauces. In membranous laryngitis stenosis begins gently (except in those cases which ascend from the bronchi) and increases gradually; there are, it is true, remissions in the {104} morning (mostly), but they are but slight, and the subsequent evenings are worse than the previous ones. It increases from day to day until a slight cyanotic hue of the lips is followed with more general cyanosis. There is no fever or very little, except in the cases of generalized diphtheria. The character of the cough does not change; perhaps it becomes more dry and suppressed after a while. Hoarseness does not improve, but increases steadily into aphonia. Expectoration is but scanty; now and then a small portion of mucus from the lower portion of the respiratory tract, now and then shreds of membrane, are expelled.