=Fractures limited to the internal table.= These fractures are even more rare than those described above. Their occurrence is probably only possible when the bullet strikes the skull in a markedly oblique direction, and with greatly diminished velocity--‘spent’ bullets. I believe I am correct in stating that only one instance of this particular variety of fracture was observed in the South African War. In any case, they are of such infrequent occurrence that they may be practically disregarded. =Gutter fractures.= Gutter fractures are almost invariably dependent on the impact of a glancing bullet. They may be arranged in three groups, according to the extent of the osseous lesion. 1. Where the external table is blown away, leaving the internal table exposed, perhaps comminuted. 2. Where the internal table is driven in the inward direction, pressing on, irritating, and perhaps lacerating the dura mater. 3. Where the whole thickness of the bone is blown away, leaving a gaping wound from which brain-matter may protrude. [Illustration: FIG. 87. DIAGRAMMATIC ILLUSTRATION OF THE THREE FORMS OF ‘GUTTER’ FRACTURE. (For further description, see text.)] =The complete fractures produced by penetrating and perforating wounds.= The general effects as produced by penetrating and perforating bullet-wounds of the skull and brain are depicted in Fig. 88, and described in the text associated with that figure. =Injury to the brain.= Brain lesions vary ‘from a single track with small points of extravasation in neighbouring areas to a condition of hæmorrhagic pulp, which latter condition is the result of injury from the projectile associated with bleeding, often extensive, into neighbouring areas, disintegrating and pulping the brain-substance. These latter cases are generally fatal, and are accompanied not infrequently with meningeal and ventricular hæmorrhage’ (Bowlby).[59] The worst degrees of brain-injury arise when the injury is inflicted at close range, more especially at the site of emergence of a perforating bullet, the damage to the soft parts being there magnified by the waves and vibrations set up by the bullet during its passage across the brain. In many cases also the brain is dashed as a whole against the opposing osseous barrier (laceration by contre-coup). The general effects produced on the skull and brain by a perforating bullet of high velocity are shown in Fig. 88. =Symptomatology.= It is unnecessary to enter into details with regard to the symptoms arising from bullet-wounds of the skull and brain, for they closely resemble those previously enumerated in the chapters dealing with fractures of the skull and injury to the brain. There are, however, a few special points to which attention should be directed. 1. External hæmorrhages are seldom profuse.