In the cases which develop more slowly, and as the result of cold and chill whether in horses or cattle, there is dullness, anorexia, prostration, increasing rapidity and oppression of the breathing, a small, frequent, hoarse cough, and at first distinct pallor of the conjunctiva and pituitary mucosa, with more or less trembling. The head is extended on the neck, toward an open door or window, if available, until prostration and stupor forbid. The pulse is small, thready, often almost imperceptible and much accelerated, while the heart beats are strong, violent, tumultuous. For a time the respiration may be not more than double the normal rythm, but it tends to more or less rapid increase with wheezing or stertorous sounds and shaken by trembling of the respiratory muscles. The nasal discharge is slight and grayish often with streaks of blood. If it increases the cough becomes looser and softer. Quite early the respiratory murmur decreases over the whole lung and a blowing sound from the bronchia or larnyx is heard on the upper middle third of the chest. This may be complicated by a mucous râle, or when hæmorrhage has supervened by a loud rattling. Percussion shows a lack of resonance over the whole lung, not so flat and definitely circumscribed as in pneumonia but a partial flatness of sound over the whole chest. In pneumonia a limited area of lung is absolutely solidified (hepatized) while the remaining lung is practically normal, whereas in acute congestion often the whole lung is gorged with blood but for some time no part of it is entirely divested of air. Another marked feature is the maintenance at first of the normal temperature with only a slight rise of about 1°. This serves to distinguish congestion of the lungs from sunstroke (heat anhæmatosis) in which the temperature usually rises to 108° or 110° F or higher. The temperature rises however as the disease advances and merges into pneumonia. Another distinguishing feature from sunstroke is the early pallor of the mucous membranes which in heat apoplexy are strongly congested. In congestion they become dark red only with the advance of the disease and the advent of asphyxia. These features serve also to distinguish acute pulmonary congestion from contagious fevers, pneumonia and other inflammations of internal organs. _Course._ _Termination._ The more acute (fulminant) forms are promptly fatal. In the exhausted system the lungs have become uniformly gorged with blood, which can no longer be forced through the capillaries by the right heart, the heart in turn is overdistended with blood and ceases to beat and death ensues in a few minutes. In the less acute cases the patient survives twenty-four hours and upward, the whole lung not being equally implicated but only certain lobules, usually the lower, or the congestion, if uniform in all the lung, being less extreme.