In these doubtful cases the surgeon is greatly aided in his decision by a general review of the patient’s condition, more especially by those symptoms which are regarded as exemplifying the clinical conditions of concussion, irritation, and compression. _When the fracture is associated with mild concussion_ it may be inferred that the brain is practically uninjured, and that operative treatment is not required. _When the fracture is associated with severe concussion_ it may be inferred that the brain is damaged, to a degree proportionate to the depth and duration of the stage of unconsciousness. The question of operation depends to a very large extent on the general condition of the patient, and more especially on the temperature and temperature changes (see p. 114). With a persistent subnormal temperature it may be inferred that the brain-injury is of a very severe nature, and that operative measures are, for the time being, contra-indicated. In the event of the temperature rising it may be accepted that the patient is passing from the state of shock to that of reaction, operative measures again hinging on the further progress of the case. If the temperature rises progressively, the patient passing from the stage of reaction to that of compression, operative measures are indicated. Under other circumstances an expectant attitude can be adopted. _When the fracture is associated with general cerebral irritation_ it may be inferred that the brain is contused or slightly lacerated. Under these circumstances operation is, for the time being, not required, and an expectant attitude should be adopted. _When the fracture is associated with compression_ it may be inferred that the condition is dependent on depressed fragments of bone, or on extra- or intra-dural bleeding. Operative measures are now urgently indicated. _When the fracture is confined to the internal table_ a diagnosis is only possible when symptoms of localized irritation ensue, either due to pressure exercised on the cortex by spicules of bone or resulting from injury to some intracranial vessel, e. g. the middle meningeal artery. In such cases operation is indicated. Under other circumstances the surgeon must await the developments of the case.