In this variety the characteristic symptoms may be much less marked and the disease is less easily recognized. There is some acceleration and quickness of pulse, lifting of the flanks and heat of the mouth and body generally. There are alternations of heat and cold of the surface and extremities, a rough, unthrifty coat, hidebound, a dull, listless moping manner and the same symptoms on auscultation and percussion as in the acute form. The changes take place slowly but the disease may prove obstinate and is often followed by permanent alterations in the lungs. Rheumatic affections of the limbs, inflammation of the feet, and other diseases frequently supervene during the course of this form of the affection. The =terminations= of pneumonia are:—by =death=; =resolution= with absorption of exuded products:—=splenisation=; =abscess=; =gangrene=; permanent consolidation with organization of exuded products. The disease will sometimes lapse into the chronic form. =Death= is fortunately the least frequent issue. It may follow on rapidly advancing and general congestion of the lung,—asphyxia; from heart failure, the overworked organ becoming exhausted under the strain of forcing the blood through the virtually impervious lungs; from hyperthermia, the limit of bodily temperature 108°F. having been reached or exceeded; or from collapse and exhaustion. In =resolution= which is the most favorable termination the febrile and other symptoms subside and the exudations in the effused lung undergo a process of liquefaction and absorption until neither auscultation, nor percussion nor even the examination of the lung after death will show the slightest trace of the pre-existent disease. This is the most common termination in single pneumonia in the horse. =Splenisation= is that condition of lung already described under the head of _pulmonary congestion_, and if affecting both lungs throughout, necessarily destroys life by arresting the æration of the blood. =Abscess.= Diffuse suppuration is very common in the stage of gray hepatization. In this the affected lung becomes more or less extensively infiltrated with pus limited by no distinct membrane like the pus of an abscess, but exuding freely from the cut surface of the lung or escaping from its interstices when it is pressed. It is preceded and in its early stages associated with the formation of granular masses and corpuscles. Its existence cannot be certainly ascertained though it may be surmised when after hepatization of a portion of lung a _mucous râle_, a sort of gurgling, is heard in the adjacent bronchium and an abundant muco-purulent discharge takes place from the nose. It threatens extensive destruction of lung tissue.