_Cerebellum_—examine with same care, and note same points as in cerebrum.] =Inflammation.= Acute inflammation of the brain substance is a rare disease, except as the result of mechanical injury. In such cases, the disease is generally quite circumscribed, being confined to the immediate region of the injury. The brain becomes very vascular, acquiring a red color, which, at a later period, changes to a brown or greenish hue, and becomes much softer than natural. If a foreign body be lodged in the brain, as a piece of bone, or a bullet, then the inflammation is likely to result in an _abscess_, which will give rise to head-ache, delirium with intolerance of light, succeeded by convulsions, coma and death. _Subacute, or chronic_ inflammation of the brain, is much more common, yet is accompanied with pathological changes similar to those of the acute form. At first, the inflamed portion becomes red and congested, the color gradually changing to a crimson, purple, brown, or claret color, with more or less change of consistence. The symptoms attending inflammation of the brain substance, or _cerebritis_, are not readily distinguishable from those of meningitis; indeed, in most instances the two diseases are, to a certain extent, combined; as, from the vascular connection between the brain and pia mater, there might be a ready extension of inflammation from one to the other. When, however, there is any sudden perversion of the sense of vision or hearing; or if there are convulsions, affecting mainly one side of the body; or if coma succeeds the convulsions and is accompanied by one-sided paralysis, we may expect to find evidence of inflammation of the cerebral substance, with possibly that of the membranes also. It is a fact to be borne in mind, however, that while in typhus and typhoid, and perhaps some other forms of fever, we may have symptoms strongly resembling those of idiopathic inflammation of the brain or its membranes, still the post-mortem will reveal no trace of any such morbid condition.