The introduction of antibiotics has practically eliminated infection of the paranasal sinuses as source of intracranial infeetions. Thoracic surgery has nearly eradieated a for merly fairly frequent source of abseess of the brain, namely infections of the lung, such as lung abscess, bronchiectasia and lung gangrene. Gunshot wounds of the head are of course a very important course of brain abseess and meningitis, but in civilian practice fortunately rare. Complieated fractures of the vault and fractures of the base of the skull are at present the most important source of intraeranial infection, and are likely to increase in importance due to ever increasing frequeney of motor accidents. Metastatic brain abscess originating from a foeus of infection of the tonsils or from other lesions anywhere in the body are on the whole rare. This source of infection must be considered to be of minor importance. These faets are clearly reflected in Dr. IRSIGLER'S monograph. There is an abundance of material of traumatic abscesses both due to gunshot wounds and to pcaee-time acci dents involving the vault, the base of the skull and the paranasal sinuses, which is exten sively documented by case histories and weil chosen illustrations.

A. The rhinogenous class

B. The convexity class
C. The otogenous class
D. Metastatic brain abscesses
E. Fungal infections
Tables.