_Prognosis._ Under rational treatment about one-fourth recover. One-half of the victims make a partial recovery but remain in a condition of dementia or hebetude, blindness, deafness, local or general paralysis which renders them more or less useless. Not more than one-fifth or at most one-fourth of all cases recover. Even in these there is left an increased predisposition to recurrence. It is noted by Trasbot that the mortality is higher in highbred, nervous, irritable animals, which show a tendency to greater frequency, force and duration of the paroxysms of excitement. When decubitus is constant, death may take place from septic poisoning starting from bed sores, and gangrenous sloughing. In other cases there is fatal starvation from inability to eat. _Lesions._ In =pachymeningitis= due to mechanical injury there is usually cutaneous and subcutaneous, blood extravasation, and there may be fracture of the cranial bones. The dura mater is dark red, hyperæmic, thickened, covered with exudation and small blood clots mixed with pus cells, and has contracted strong adhesions to the cranial bone. Bony spicula may project into the fibrous neoplasm. =Leptomeningitis= usually coexists from extension of the inflammation into the adjacent arachnoid and pia mater. There is then a reddish serous effusion into the arachnoid and beneath it, and the substance of both membranes is thickened by exudate, and discolored by congestion and minute hæmorrhages. Whenever the pia mater is thus inflamed, the superficial layer of the brain is implicated, œdematous, soft and doughy. The extension is also made into the ventricles and a serous effusion takes place often to two, three or more times the normal amount (82 grammes Schütz). The choroid plexus forms a yellowish gelatinoid mass, and the ganglia (corpora striata, optic thalamus, etc.), are flattened. In =encephalitis= the affected superficial gray matter of the ganglia or convolutions, is deepened in color, usually in limited areas corresponding to the disease of the meninges. Sometimes the color becomes of a distinctly reddish tinge, and when cut into shows unusually prominent red points where the capillaries have been cut. Somewhat larger areas of blood staining indicate hæmorrhagic extravasations. The nervous substance is more or less infiltrated with liquid and softened. The nerve cells are swollen, and in process of granular degeneration and the same is true of the myelin, while the axis cylinder is uneven in its outline. Apart from the numerous minute petechial hæmorrhages there is an abundant migration of leucocytes which are found scattered in the degenerating and softened nervous tissues.