SKULL, SURGERY OF. Fractures of the vault of the skull may occur without the bone being driven in to compress the brain, and in such cases their existence may be revealed only after death. But if there is also a severe scalp wound the line of frac ture may be traced in the bare bone as a thin red crack. The patient with a suspected fracture of the skull is put to bed in a dark, quiet room, and is watched. It may be that the crack has extended across a bony groove in which an artery is running, and, the artery being torn, haemorrhage may take place within the skull and symptoms of compression of the brain may supervene.
Compression of the brain may be the direct and immediate result of a head-injury, a piece of the vault of the skull being driven in, and a local or a general paralysis of muscles being at once observed. In addition to the muscular paralysis, there may be insensibility, laborious breathing, dilated pupils that do not react to light. In such cases the treatment is trephining.
Fractures of the base of the skull are always serious, in that they may run across important nerves and large blood-vessels; passing through the roof of the nose, or the ear, they may corn municate with air-cavities. Thus, the dangers of sepsis are added to those of concussion or compression of the brain. Fractures of the base of the skull are often associated with bleeding from the nose, mouth or ear, or with extravasation of blood over the eyeball. Facial paralysis is the result of the line of fracture passing across the bony channel in which the seventh or facial nerve is running. When the fracture passes across the temporal bone and the middle ear, and ruptures the membrane of the tym panum, not only blood may escape from the ear, but an appar ently unlimited amount of cerebrospinal fluid. When the frac ture extends through the anterior part of the base of the skull this same clear fluid may escape from the nose. In both cases its
appearance implies that the dura mater has been lacerated and the sub-dural space opened.
Concussion of the brain (stunning) may result from a blow upon the head or from a fall from a height. The symptoms may be those of mere giddiness and a feeling of stupidity, which may quickly pass off, or they may be those of severe shock (see SHOCK). The person may die from the concussion, or he may slowly or quickly recover. As a rule, the pupils react to light. One of the first signs of returning consciousness is that the per son vomits, and after this he gradually comes round. As a result of the injury, however, he may remain irritable, liable to headache or to lapses of memory. See also BRAIN, SURGERY OF.
(Scutelktria), the corn mon name for a numerous genus of herbs and subshrubs of the mint family (Labi atae, q.v.), comprising some zoo species of nearly world-wide distribution. They have numerous blue, violet, yellow, scarlet or white flowers, borne in opposite pairs or in axillary or terminal, slender, one sided spikelike racemes. The corolla has a long tube, dilated at the throat and surmounted with two unequal lips, the upper usually entire and the lower notched. The persist ent calyx bears a conspicuous protuberance on the upper lip, giv ing it a helmet-like appearance, whence the common name. Two species occur in the British Isles, the common or marsh skull-cap (S. galericulata), with handsome violet-blue flowers, and the lesser skull-cap (S. minor). Besides the common skull-cap, which is found across the continent, some 25 other species occur in North America.